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The trinity is in the old testament

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After not so many votes...

It's a tie!
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Since my previous debate on the trinity went well for me I decided to do another one.

Pro:

* Pro trinity in the old testament

Con:

* can be Jewish, unitarian, or other similar group

rules:

* use old testament verses as sources
* New testaments are acceptable but primarily use old testament sources
* Talmudic and other rabbinic commentaries are also acceptable sources
* The more evidence the bigger are the chances to win.
* avoid logical fallacies
* avoid insults
* respond quickly and effectively(less than 1 day recommended)

Round 1
Pro
General
Genesis 1:26: "Then God said, “Let Us make man in Our image, according to Our likeness; let them have dominion over the fish of the sea, over the birds of the air, and over the cattle, over all the earth and over every creeping thing that creeps on the earth.”"

Instead of saying "I will" God says "let us", We can say that there are other gods, but this would not be biblical since God is the only god(Deuteronomy 6:4). We can also say that angels helped God, but angels cannot create living things like God can.  

Messiah/ the son

Also the Hebrew bible also states that the messiah would come from a past-eternal source(God) in Micah 5:2 - which states:
"“But you, Bethlehem Ephrathah, Though you are little among the thousands of Judah, Yet out of you shall come forth to Me The One to be Ruler in Israel, Whose goings forth are from of old, From everlasting.”"

Most Jews believe that God doesn't have a son, but they are wrong. A mention of the son of God is all over the Hebrew bible:

Psalm 2:7 - "I will tell of the decree: The Lord said to me, “You are my Son; today I have begotten you."

Isaiah 9:6 - "For to us a child is born, to us a son is given; and the government shall be upon his shoulder, and his name shall be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace."

2 Samuel 7:14 - "I will be to him a father, and he shall be to me a son. When he commits iniquity, I will discipline him with the rod of men, with the stripes of the sons of men,"

Isaiah 7:14 - "Therefore the Lord himself will give you a sign. Behold, the virgin shall conceive and bear a son, and shall call his name Immanuel."

Micah 5:2 - "But you, O Bethlehem Ephrathah, who are too little to be among the clans of Judah, from you shall come forth for me one who is to be ruler in Israel, whose coming forth is from of old, from ancient days." As you see here, the messiah will come from a primordial/ancient source. This ancient source is God.

There is also a weird character in the bible called "the angel of the lord", which is an angel in the bible that appears to several characters(Like Abraham and Sarah) and speaks like he is God. This character has been thought of as a Christophany(a non-physical appearance of Christ prior to his birth).

While there are also angels of the lord in the New testament, the angel of the lord in the Hebrew bible differs considerably. The old testament angel of YHWH speaks like he is God. Especially when he meets the Egyptian servant of Abraham in  Genesis 16:10: "Then the angel added, “I will greatly multiply your offspring so that they will be too numerous to count.”"

The passages showing this angel of YHWH is divine:

Genesis 16
Genesis 22
Genesis 31
Exodus 3
Exodus 14
Numbers 22
Judges 2
Judges 6
Judges 13
Zechariah 3
Zechariah 12

The angel of YHWH is also referred as the "word of YHWH"(Similar to how Jesus is referred to as the word of God)

The holy spirit

Isaiah 48:16 - “Come near to Me, hear this: I have not spoken in secret from the beginning; From the time that it was, I was there. And now the Lord GOD and His Spirit Have sent Me.”

The holy spirit is often personified and acts in ways that a force cannot:

Isaiah 11:2 - "And the Spirit of the Lord shall rest upon him, the Spirit of wisdom and understanding, the Spirit of counsel and might, the Spirit of knowledge and the fear of the Lord."

Ezekiel 36:26-27 - "And I will give you a new heart, and a new spirit I will put within you. And I will remove the heart of stone from your flesh and give you a heart of flesh. And I will put my Spirit within you, and cause you to walk in my statutes and be careful to obey my rules."

Zechariah 4:6 - "Then he said to me, “This is the word of the Lord to Zerubbabel: Not by might, nor by power, but by my Spirit, says the Lord of hosts."

Psalm 104:30 - " When you send forth your Spirit, they are created, and you renew the face of the ground."

Isaiah 63:10 - "But they rebelled and grieved his Holy Spirit; therefore he turned to be their enemy, and himself fought against them."

Job 33:4 - "The Spirit of God has made me, and the breath of the Almighty gives me life." But God is the creator of all, so the spirit has to be part of God. 

Nehemiah 9:20 - "You gave your good Spirit to instruct them and did not withhold your manna from their mouth and gave them water for their thirst."

Psalm 143:10 - "Teach me to do your will, for you are my God! Let your good Spirit lead me on level ground!"

Genesis 6:3 - "Then the Lord said, “My Spirit shall not abide in man forever, for he is flesh: his days shall be 120 years.”"

Ezekiel 36:27  - "And I will put my Spirit within you, and cause you to walk in my statutes and be careful to obey my rules."

As you can see in all these verses, the holy spirit is always personified. Especially in Job 33:4 it says how the holy spirit created the narrator. But any orthodox Christian or Jew knows that God is the creator of all living beings. This spirit can't be an impersonal force because he acts in ways that forces can't. You can't grieve a force, you can't rebel against a force, and a force can't lead you. The most reasonable option is that the holy spirit is a person of God. 

Many rabbis have wrestled with this concept of multiple beings each called YHWH. Here are the three persons in the old testament:

YHWH
ANGEL OF YHWH
SPIRIT OF YHWH


Ancient Jews who noticed this:

Philo of Alexandria: taught something similar to modalism or partialism, he believed that there were 3 gods who came from 1 God who created the world.

Talmud chapters about rabbis on the trinity


Jewish scholar Dr. Benjamin Sommer said  on the trinity "This is actually an old, ancient near eastern idea, that is an old, Semitic idea that is popping up again among those Jews who were the founders of Christianity"

Jews have a similar idea to the trinity in the Kabbalah were God is split into 10 sephirot. And these sephirot are split again into 10

Sommer also quoted " I came to my shock when I finished this book is that we Jews have no theological objection to the doctrine of the trinity. I came to the conclusion that we Jews have no theological right to object to the trinity."

The Talmud also has stuff to say about these old testament verses, but not all of them interpreted them the way that Christian trinitarians do, but they recognize the existence of other powers alongside God and Multiple powers each named YHWH.

In Babylonian Talmud 38b, the author is debating with a Jewish Christian who pointed to Exodus 24:1. This Christian Jew also pointed out How God said to Moses "Come up to YHWH" instead of "Come up to me".

The rabbi responded by saying that God was referring to an angel Metatron(coolest angel name) who in Judaism was the highest of all angels. This rabbi - like many others - recognized that the Hebrew bible referenced multiple figures named YHWH.

Link to this Talmudic passage: https://www.sefaria.org/Sanhedrin.38b?lang=bi


So as you can see here, I have given my attempt to prove that the trinity is an originally Jewish idea.
Con
Thank you, Pro, for your opening argument. I’ll proceed with mine.

1. General

First of all, there is one fact that I think can be established. There are no explicit references to the Trinity in the Hebrew Bible, which Christians call the Old Testament. There is no verse which refers to God being divided into three persons, or any outline of the doctrine of the Trinity. Pro has posted a collection of Bible verses which he argues implicitly point to the doctrine of the Trinity when taken together, but this supposed connection is by no means clear or unambiguous.

There are several other facts that I must establish. Firstly, the Jewish faith does not accept the doctrine of the Trinity. The oneness of God is an important tenet of Judaism. Rabbi Wayne Dosick, explaining the Jewish conception of God, states that “‘One’ means indivisible. One God cannot be broken into parts or divided into entities. No concept of duality or trinity can exist, for YHWH cannot be separated into sections”. (Living Judaism by Rabbi Wayne Dosick, pp. 7-8) The closest thing we have to a succinct, widely-accepted list of Jewish beliefs is Maimonides’ thirteen principles of faith, and the second of these states that God is only one, “not two or more”. Another fact we can agree upon is that the Hebrew Bible is the primary sacred text of the Jewish faith. Jews refer to the Hebrew Bible itself as the “Tanakh”, and single out the first five books of the Bible, the “Torah”, as especially sacred. To argue that the Holy Trinity is present in the Hebrew Bible is to argue that every Jew in history, including rabbis and Torah scholars who have pored over this text’s every word in the original language, have simply misinterpreted it.

The idea of the Trinity originates with the early church fathers. It is implied in the writing of “the Father, the Son, and the Holy Spirit”, which has been found, at the earliest, near the end of the first century. The doctrine of the Holy Trinity would not be explicitly outlined and standardized for the common Christian until the Council of Nicaea in 325 CE. Therefore, it cannot possibly be present in the Hebrew Bible, which was fully composed, at the very latest, 200 years before the earliest mentionings of the Trinity. That is, unless there is the presence of divine intervention. But unless Pro proves beyond all doubt that the Bible is the Word of God, then his argument rests on shaky ground rather than any solid proof. Now I will turn to Pro’s cited Bible verses to see if they on their own prove that the Holy Trinity is present in the Hebrew Bible.

Pro states that in Genesis 1:26, since God refers to himself in the plural, that implies that there is more than one person in the Godhead. At least, that’s how I interpreted the unfinished thought there. In reality, this is what Hebrew grammarians refer to as pluralis excellentiae, which is similar to the “royal we” in English. Nowhere in Genesis, nor indeed in the rest of the Hebrew Bible, does it imply that God is more than one, and in fact God’s oneness is explicitly asserted (Deuteronomy 6:4, Malachi 2:10, Hosea 13:4).

2. The Messiah

Pro points to the discussion of the messiah in the Hebrew Bible, but it should be noted that the Jewish conception of the messiah is completely different from Christian ideas surrounding Jesus. Jews believe that the messiah is a great person who will arise to redeem the Jewish people at some point in the future, not necessarily a son of God, and certainly not equivalent to God. Christians will often pick out verses from prophecies in the Hebrew Bible that sound similar to Christian language to “prove” that Jesus was prophesied in the Old Testament. But since Christianity was an outgrowth of Judaism and Jesus himself cited these verses, these parallels should not be surprising. But look past these cherry-picked verses and observe the bigger picture painted in Isaiah or Jeremiah, and the messiah sounds a lot more like a political figure or military leader whose focus is only on Israel, not all of humanity.

With this in mind, we can dismiss Pro’s cited verses which point only to the coming of the messiah. For similar reasons, verses which refer to “sons of God” do not necessarily point to the Trinity. The language is used in the Hebrew Bible to refer to angels or even humans. After all, God is referred to as a Father, so it makes sense from a literary standpoint to refer to any male person as a son of God. Not to mention one of Pro’s own cited verses (2 Samuel 7:14) refers to one of these sons of God as “committing iniquity”, which doesn’t sound very Christ-like. The Hebrew Bible makes no mention of the Christian idea that there is only one “Son of God”, and in fact, it is more common to see it in the plural. See Genesis 6, which describes “sons of God” having sex with human women and giving birth to creatures called the Nephilim.

Pro also points to the angel of the Lord, and the idea that it is a Christophany is simple retroactive speculation by Christians. The wording of the Bible is vague enough that there are multiple theories about the angel of the Lord as a messenger of God, a mediator between God and humans, or an avatar of God himself. Not that the Christophany theory must be immediately dismissed, but the mere existence of this character doesn’t point to the Holy Trinity.

3. The Holy Spirit

In this section, Pro simply compiles a bunch of times that the word “spirit”, or ruach, appears in the Hebrew Bible. This word is sometimes translated as “breath”, but it is often used to refer to some kind of life-force or divine energy emanating from God which may be thought to be present in pious men. This interpretation does not contradict any of the verses that Pro has cited, and while Pro seems confident that the Spirit referred to in these verses must be distinct from God the Father, I fail to see why this is so obvious. The Jewish idea of ruach haqodesh is sometimes translated as Holy Spirit, but it is not a personage and is totally different from the Holy Spirit of Christianity. The rabbinic literature states that while the Holy Spirit is personified in a couple verses in a literary sense, it remains “a quality belonging to God, one of his attributes”. While Pro may conclude from these verses that Christian doctrine is present in the Hebrew Bible, rabbis and others who study the Bible for a living disagree.

4. Jewish Opinion

Pro attempts to appeal to Jewish authority to support the Trinity’s presence in the Hebrew Bible. I am not sure what angle Pro is going for here. Is Pro trying to argue that the Jewish faith actually does accept the Trinity? It seems not, since Pro states “Most Jews believe that God doesn't have a son, but they are wrong.” But then, since Pro by necessity believes that nearly all Jewish scholars are misinterpreting the Hebrew Bible in a very blatant and obvious way, why now does he trust Jewish scholarship and the Talmud?

Pro, pulling from the Youtube video he linked, quotes Dr. Benjamin Sommer, a Jewish scholar who is sympathetic to the idea of the Trinity, and states that the Christian idea of the Trinity was similar to ancient Canaanite ideas of God. At no point does Dr. Sommer state that the Trinity is present in the Hebrew Bible, and in fact implies that it was absent in the gap between Canaanite pre-Judaic religion, and its “popping up again” among early Christians. So this really has no bearing on the main argument.

Kabbalists are a small, esoteric sect of Jews, and their ideas are not accepted by the wider Jewish community, and Kabbalah was censored for a time under the rabbis. Not to mention that even if the entire Jewish faith accepted the idea of the 10 sefirot, that is still a completely different idea from the Christian Trinity. This debate is about the presence of the Holy Trinity in the Hebrew Bible, and even if there does exist a Hebrew Bible verse which states that God has multiple incarnations, that is only a step toward the argument, that alone does not prove the specific doctrine of the Trinity. Pro’s reference to the Talmud goes back to the point about the angel of the Lord. The rabbi was not recognizing that there were multiple figures named YHWH, but referring to mal’akh YHWH, the messenger of Yahweh, or the angel of the Lord. Neither this quotation from the Talmud nor the verse it cites points to the Trinity in any obvious way.

Pro’s case that the Trinity is present in the Old Testament relies on plucking out Bible verses that use vague enough language to where it could be argued that they are referring to God as a being made up of several different personages. Not only do none of these verses explicitly point to the Holy Trinity, they can only be said to implicitly point to the Holy Trinity if one assumes from the beginning that the Bible is divinely inspired. Pro is claiming, after all, that a text composed hundreds of years before the birth of Jesus is directly referencing the Christian theology of Father, Son, and Holy Spirit. Even if we accept Pro’s claims, this only raises more questions than it answers. For example, if these verses so clearly and obviously prove the Trinity, why do Jews not accept this? Surely a large number of rabbinical scholars, who know a lot more about the Hebrew Bible than you or me, would come out in favor of the Trinity if what you are saying is true. But why don’t they? From what I can tell, there are two ways to answer this question: to admit that there is ambiguity in the text, or to argue that Jews as a religious group are unreasonable or ignorant in some way.
Round 2
Pro
Section 1

First of all, there is one fact that I think can be established. There are no explicit references to the Trinity in the Hebrew Bible, which Christians call the Old Testament. There is no verse which refers to God being divided into three persons, or any outline of the doctrine of the Trinity. Pro has posted a collection of Bible verses which he argues implicitly point to the doctrine of the Trinity when taken together, but this supposed connection is by no means clear or unambiguous.

Neither are there explicit references to the trinity in the new testament. The bible doesn't need to have the word "trinity" to know that there's a trinity just like you don't need to refer to a person as a "human" to know that that person's a human. If it looks like a duck, acts like a duck, sounds like a duck, then it's probably a duck. Each of the verses is either evidence for a person of a trinity or evidence that the person is part of a trinity. God often refers as himself as "the lord" instead of "I".

There are several other facts that I must establish. Firstly, the Jewish faith does not accept the doctrine of the Trinity. The oneness of God is an important tenet of Judaism.
This does not matter, Jews became unitarians as a response to Christianity. The oneness of God is only a tenet of modern Judaism. If the prophets of the hebrew bible were to look at modern Jews then they would seem alien to the prophets. As I previously stated, rabbis throughout history have wrestled with the concept of the multiple persons of God in the Hebrew bible and their belief in Unitarianism.

Judaism. Rabbi Wayne Dosick, explaining the Jewish conception of God, states that “‘One’ means indivisible. One God cannot be broken into parts or divided into entities.
First of all the word for one in "the lord is one" does not actually refer to total unity. It means that God is the only god. Also the trinity is not a division or a breaking of parts. The idea that the 3 persons of the trinity are parts of God is a heresy called partialism. God is one being with three persons. 

The idea of the Trinity originates with the early church fathers.
It doesn't, Philo of Alexandria as I said prior taught something similar to modalism. The trinity is an overlay term for a complicated relationship between god and his 3 persons.

It is implied in the writing of “the Father, the Son, and the Holy Spirit”, which has been found, at the earliest, near the end of the first century.
The bible is often believed to be written in progressive revelation. That means that the more you read of the bible, the more about God and the universe is revealed. The trinity existed in the oldest Hebrew scriptures prior to being revealed in the New Testament.

Trinity. That is, unless there is the presence of divine intervention. But unless Pro proves beyond all doubt that the Bible is the Word of God, then his argument rests on shaky ground rather than any solid proof. Now I will turn to Pro’s cited Bible verses to see if they on their own prove that the Holy Trinity is present in the Hebrew Bible.
This debate is not about whether the bible is the word of God but I'll give some evidence that it is.:

  • There are a couple of verses in Isaiah that describe God as expanding the heavens. Then in 1929 Edwin Hubble discovered redshift and that the universe was expanding.
  • The oldest nigh complete copy of Isaiah is found in the dead sea scrolls, which predate Jesus. There is no way that people of the time could prove that the universe was expanding.

Pro states that in Genesis 1:26, since God refers to himself in the plural, that implies that there is more than one person in the Godhead. At least, that’s how I interpreted the unfinished thought there. In reality, this is what Hebrew grammarians refer to as pluralis excellentiae, which is similar to the “royal we” in English. Nowhere in Genesis, nor indeed in the rest of the Hebrew Bible, does it imply that God is more than one, and in fact God’s oneness is explicitly asserted (Deuteronomy 6:4, Malachi 2:10, Hosea 13:4).
Deuteronomy 6:4 - This verse is too short to imply Unitarianism, the word for one here can be used to say "one army".  This verse is also translated "The LORD our God is one Lord,” ". Nowhere in the old testament is there a verse that prohibits the existence of the trinity. 

Malachi 2:10 - 10 Have we not all one father? hath not one God created us? why do we deal treacherously every man against his brother, by profaning the covenant of our fathers?
This verse does not disprove the trinity. This verse is stating that we all come from one God. This verse does not deny the trinity which states that there is 1 God with 3 persons. 1 father doesn't deny the trinity because father is a title for God in general. God is 3. 
Hosea 13:4  I am the Lord thy God from the land of Egypt, and thou shalt know no god but me: for there is no saviour beside me.
The trinity aren't different gods, just 1 God with 3 persons. This verse does not deny the trinity and simply states "I am the only God and the only one who can save you".

your argument here was pretty weak.

Section 2

Pro points to the discussion of the messiah in the Hebrew Bible, but it should be noted that the Jewish conception of the messiah is completely different from Christian ideas surrounding Jesus. Jews believe that the messiah is a great person who will arise to redeem the Jewish people at some point in the future, not necessarily a son of God, and certainly not equivalent to God.
This is exactly what Jesus did. Jesus was more than a great person and he came to redeem the world as in John 3:17.
For God did not send his Son into the world to condemn the world, but to save the world through him.
The idea that the messiah will come in the future is barely a difference and does not deny his existence prior to his coming as stated in Micah 5:2
“But you, Bethlehem Ephrathah,
    though you are small among the clans of Judah,
out of you will come for me
    one who will be ruler over Israel,
whose origins are from of old,
    from ancient times.”
Anyways moving on.

But since Christianity was an outgrowth of Judaism and Jesus himself cited these verses, these parallels should not be surprising. But look past these cherry-picked verses and observe the bigger picture painted in Isaiah or Jeremiah, and the messiah sounds a lot more like a political figure or military leader whose focus is only on Israel, not all of humanity.
First of all, Does this prophecy of the messiah sound like a powerful political leader to you? Isaiah 53:
Who has believed our message
    and to whom has the arm of the Lord been revealed?
2 He grew up before him like a tender shoot,
    and like a root out of dry ground.
He had no beauty or majesty to attract us to him,
    nothing in his appearance that we should desire him.
3 He was despised and rejected by mankind,
    a man of suffering, and familiar with pain.
Like one from whom people hide their faces
    he was despised, and we held him in low esteem.
4 Surely he took up our pain
    and bore our suffering,
yet we considered him punished by God,
    stricken by him, and afflicted.
5 But he was pierced for our transgressions,
    he was crushed for our iniquities;
the punishment that brought us peace was on him,
    and by his wounds we are healed.
6 We all, like sheep, have gone astray,
    each of us has turned to our own way;
and the Lord has laid on him
    the iniquity of us all.
7 He was oppressed and afflicted,
    yet he did not open his mouth;
he was led like a lamb to the slaughter,
    and as a sheep before its shearers is silent,
    so he did not open his mouth.
8 By oppression[a] and judgment he was taken away.
    Yet who of his generation protested?
For he was cut off from the land of the living;
    for the transgression of my people he was punished.[b]
9 He was assigned a grave with the wicked,
    and with the rich in his death,
though he had done no violence,
    nor was any deceit in his mouth.
10 Yet it was the Lord’s will to crush him and cause him to suffer,
    and though the Lord makes[c] his life an offering for sin,
he will see his offspring and prolong his days,
    and the will of the Lord will prosper in his hand.
11 After he has suffered,
    he will see the light of life[d] and be satisfied[e];
by his knowledge[f] my righteous servant will justify many,
    and he will bear their iniquities.
12 Therefore I will give him a portion among the great,[g]
    and he will divide the spoils with the strong,[h]
because he poured out his life unto death,
    and was numbered with the transgressors.
For he bore the sin of many,
    and made intercession for the transgressors.
Also don't come out and say that this is about Israel because the idea that this passage is about Israel is a new idea. The ancient rabbis all believed that this was about the messiah. Second of all, God chose Abraham's family(the Jews) and through them he wants to redeem the entire world(Genesis 12:1-20) and Jesus is the fulfillment of this promise. So when Israel was redeemed then all of humanity is redeemed.

With this in mind, we can dismiss Pro’s cited verses which point only to the coming of the messiah. For similar reasons, verses which refer to “sons of God” do not necessarily point to the Trinity.
These sons of God are angels. There can only be 1 begotten son(John 3:16). The 1st difference is that these sons of god are only referred to once, the son of God is referred to often. The son of God is
Pro also points to the angel of the Lord, and the idea that it is a Christophany is simple retroactive speculation by Christians. The wording of the Bible is vague enough that there are multiple theories about the angel of the Lord as a messenger of God, a mediator between God and humans, or an avatar of God himself. Not that the Christophany theory must be immediately dismissed, but the mere existence of this character doesn’t point to the Holy Trinity.
This is wrong. The character does point to the existence of the trinity. and here are the reasons:

Section 3

In this section, Pro simply compiles a bunch of times that the word “spirit”


More specifically "Spirit of God"
This word is sometimes translated as “breath”, but it is often used to refer to some kind of life-force or divine energy emanating from God which may be thought to be present in pious men.
As I stated before, the spirit is more than a force. It it written like its a person and acts like a person

Section 4

Pro attempts to appeal to Jewish authority to support the Trinity’s presence in the Hebrew Bible. I am not sure what angle Pro is going for here. Is Pro trying to argue that the Jewish faith actually does accept the Trinity? It seems not, since Pro states “Most Jews believe that God doesn't have a son, but they are wrong.” But then, since Pro by necessity believes that nearly all Jewish scholars are misinterpreting the Hebrew Bible in a very blatant and obvious way, why now does he trust Jewish scholarship and the Talmud?
While Jewish authorities are humans, you can still use them to see how they treat these particular verses. The responses are interesting. When I said “Most Jews believe that God doesn't have a son, but they are wrong.” I didn't mean that all of them are wrong or that they are wrong on everything. The Jews referred here are mostly laymen of the reform or secular branches of Judaism - these people don't often read scripture and use tradition instead. I don't recommend using Jewish traditions for all of your proof against me, it is better to rely on the Jewish scriptures.

Pro, pulling from the Youtube video he linked, quotes Dr. Benjamin Sommer, a Jewish scholar who is sympathetic to the idea of the Trinity, and states that the Christian idea of the Trinity was similar to ancient Canaanite ideas of God. At no point does Dr. Sommer state that the Trinity is present in the Hebrew Bible, and in fact implies that it was absent in the gap between Canaanite pre-Judaic religion, and its “popping up again” among early Christians. So this really has no bearing on the main argument.

Dr. Benjamin Sommer is still a Jew and a Jewish scholar, which means he is a Jewish authority.

Kabbalists are a small, esoteric sect of Jews, and their ideas are not accepted by the wider Jewish community, and Kabbalah was censored for a time under the rabbis. Not to mention that even if the entire Jewish faith accepted the idea of the 10 sefirot, that is still a completely different idea from the Christian Trinity. This debate is about the presence of the Holy Trinity in the Hebrew Bible, and even if there does exist a Hebrew Bible verse which states that God has multiple incarnations, that is only a step toward the argument, that alone does not prove the specific doctrine of the Trinity. Pro’s reference to the Talmud goes back to the point about the angel of the Lord. The rabbi was not recognizing that there were multiple figures named YHWH, but referring to mal’akh YHWH, the messenger of Yahweh, or the angel of the Lord. Neither this quotation from the Talmud nor the verse it cites points to the Trinity in any obvious way.

You are missing the point, the comparison of the trinity to Kabbalah is used to state that just like Kabbalah the trinity is not a fully pagan idea and has Jewish origin. Even if the Kabbalah isn't accepted by all Jews, it is still a Jewish idea.

Pro’s case that the Trinity is present in the Old Testament relies on plucking out Bible verses that use vague enough language to where it could be argued that they are referring to God as a being made up of several different personages.

The bible verses were not plucked, they were read in context. And there are many verses, so the possibility of a trinity is likely. These verses have stumped the rabbis throughout the ages. Their responses were interesting, for example: The angel of the lord is believed to be the metatron by the Rabbis.

For example, if these verses so clearly and obviously prove the Trinity, why do Jews not accept this?
Because relations between Christians and Jews throughout history were tense. The reason that they don't accept it is because even to this day Jews don't want to identify with Christianity. The trinity is a misunderstood idea and to many Jews it seems pagan.

From what I can tell, there are two ways to answer this question: to admit that there is ambiguity in the text, or to argue that Jews as a religious group are unreasonable or ignorant in some way.
As for the first answer, the bible is seen as being ambiguous at the beginning and later revealing more of God(this is progressive revelation). As for the second way, The Jews are humans, they are able to sin and make mistakes and their bias will affect the way they view the bible.
Con
Thank you for your response, Pro. I must start off by pointing out that in Round 2, my opponent has made much use of pointing out that the Hebrew Bible “doesn’t disprove” the notion of the Trinity. That isn’t sufficient. Remember that you are arguing that the Trinity is present in the Hebrew Bible, and the burden of proof is on you to demonstrate this. My job is to demonstrate that these proofs are insufficient and that these verses are talking about things other than the Trinity. Expecting me to find verses that somehow disprove the Trinity is something beyond the scope of the debate.

Pro has ignored a lot of the larger points I had made, and much of his rebuttal in Round 2 has been directed at individual, minor statements. Therefore, the points he has not responded to still stand, and I will reiterate them in the conclusion.

This does not matter, Jews became unitarians as a response to Christianity. The oneness of God is only a tenet of modern Judaism. If the prophets of the hebrew bible were to look at modern Jews then they would seem alien to the prophets. As I previously stated, rabbis throughout history have wrestled with the concept of the multiple persons of God in the Hebrew bible and their belief in Unitarianism.
As far as I can see, this is a series of unsubstantiated statements. What proof do you have that “Jews became unitarians as a response to Christianity”? When did you state that “rabbis throughout history have wrestled with the concept of the multiple persons of God”, other than one example you gave which was about a completely unrelated topic? We cannot simply make up facts in order to support our worldview without any sources whatsoever.

There are a couple of verses in Isaiah that describe God as expanding the heavens. Then in 1929 Edwin Hubble discovered redshift and that the universe was expanding. …
The oldest nigh complete copy of Isaiah is found in the dead sea scrolls, which predate Jesus. There is no way that people of the time could prove that the universe was expanding.
Perhaps Pro was right that we should keep discussion of whether or not the Bible is the word of God out of it. The idea that Isaiah 40:22 (“He stretches out the heavens like a canopy, and spreads them out like a tent to live in”) must refer to the universe’s expansion is incredibly weak. Is that really the only possible interpretation that an educated person would take from this verse? The idea of God “stretching out the heavens like a canopy” over the “circle of the earth” is simply poetic language. The sky has often been described as a ceiling or canopy above the Earth in the pre-modern world, and indeed the ancient Hebrews thought of Earth as a flat circle and the sky as a dome encasing it. Which sounds a lot more similar to the verse cited than the current scientific model of an impossibly vast universe that is constantly expanding. Nowhere in the verse does it mention any constant expansion of the heavens. And even if it did, why does this automatically mean the Bible is the word of God? Could this not simply be a coincidence? For example, the Quran can be said to predict Hubble’s same theory that the universe is expanding and all its objects are moving away from one another: “Have those who disbelieved not considered that the heavens and the earth were a joined entity, and We separated them”. (Quran, 21:30) These words of Allah hint not only at cosmic expansion, but the Big Bang. So then, does that mean the Quran is the word of God too? If not, then why not? Pro can answer these questions if he wishes, but perhaps we should keep our focus on the main topic.

As a small word of advice for you to succeed in future debates, Pro, I suggest you be on the lookout for confirmation bias. It’s something that all humans do: applying little skepticism and accepting sloppy logic from evidence that supports your worldview, and applying harsh skepticism and scrutinizing every logical detail of evidence that seems to go against your worldview. Everyone does it to an extent, and it is something to strive to overcome. Especially on this site, since people here are more alert to it than most. I have noticed it from you in our past two debates. I am not going to formally accuse you of committing a fallacy, but I’m telling you this because the people here tend to pick up on fallacious thinking and vote against it. All I’m saying is: strive to evaluate all evidence equally, whether it supports or goes against your beliefs. A lot of talented conservative/religious debaters, such as William Lane Craig, are good at doing this.

Nowhere in the old testament is there a verse that prohibits the existence of the trinity.
With regards to Pro’s response to the three verses we cited proclaiming God’s oneness, Pro seems to think that I meant these verses to debunk the idea of the Trinity. On the contrary, we cited these verses to defend the idea that God’s oneness is an idea that is well-rooted and established in ancient Judaism, rather than a “modern idea” as Pro says. Of course these verses do not “disprove” the Trinity, because the Trinity was not invented as an idea yet. And an atheist would argue that the idea of the Trinity was specifically tailored not to explicitly contradict the Hebrew Bible, since, after all, Christians believe that the God of the Old and New Testaments is one and the same. The idea of the Trinity is famously so complex, God being one and three at the same time, that many believers have trouble wrapping their heads around it. The writers of the Hebrew Bible could not possibly have anticipated this complicated premise in order to denounce it. All this is to say that my job is not to demonstrate that the Hebrew Bible disproves the Trinity, but that it contains no mention of it. Again, the burden of proof is on Pro.

First of all, Does this prophecy of the messiah sound like a powerful political leader to you? Isaiah 53:
The chapter you just quoted there is not talking about the messiah. It is one of the four servant songs, each of which is written about an unnamed “servant of Yahweh”, whose identity remains ambiguous and subject to various interpretations. Christians, of course, assume that it is a supernatural prophecy of Jesus. The modern Jewish view is that the “servant” is an allegory for the nation of Israel itself. Some believe that it is indeed referring to the Jewish messiah, or the king Hezekiah. In any case, nowhere in Isaiah 53 is this figure equated with God, and it is completely possible for a political leader to be despised, rejected, and subject to suffering.

Also don't come out and say that this is about Israel because the idea that this passage is about Israel is a new idea. The ancient rabbis all believed that this was about the messiah.
I have no opinion about who or what Isaiah 53 is referring to. All I am arguing is that the passage is vague enough to open itself up to multiple interpretations, therefore it cannot be said to definitively prove the Trinity’s presence in the Hebrew Bible. We would also add that both of your statements here are completely unsubstantiated. What source do you have to prove that “the ancient rabbis all believed that this was about the messiah”?

This is wrong. The character does point to the existence of the trinity. and here are the reasons: The angel speaks like if he's God … This angel acts like he's God
Again, this does not contradict my point at all. It is true that in multiple verses the angel speaks as if he is God. But how does that contradict the angel being a messenger of God? After all, it is a messenger’s job to speak on behalf of the person composing the message. Perhaps God is choosing to speak through this angel, just as God has spoken through several beings in the Bible, such as Balaam’s donkey (Numbers 22:21-3). Or it may just be an earthly manifestation or avatar of God. Both of these views are perfectly valid and accepted by the Jewish faith. To jump to the conclusion that it must be a separate person of God and then latch on immediately to the Christ theory is not a product of sober, critical examination. We cannot brush aside all other possible interpretations simply because they do not conform to our own pre-existing beliefs.

As I stated before, the spirit is more than a force. It it [sic] written like its a person and acts like a person
Then we will simply have to agree to disagree. I do not necessarily see how it’s written like a person or acts like a person, except for mild personification in a couple verses. But as I said before, the rabbis maintain that the Spirit is “a quality belonging to God”, so as long as this interpretation remains open, it cannot be said that these verses must refer to the Trinity.

I don't recommend using Jewish traditions for all of your proof against me, it is better to rely on the Jewish scriptures.
You are the one who said “Talmudic and other rabbinic commentaries are also acceptable sources”.

Dr. Benjamin Sommer is still a Jew and a Jewish scholar, which means he is a Jewish authority.
And again, I will reiterate, Dr. Sommer never said that the Trinity is present in the Hebrew Bible, but that the doctrine of the Trinity has interesting connections with Canaanite semi-polytheistic religious traditions that predate Judaism. This is unrelated to the main argument.

You are missing the point, the comparison of the trinity to Kabbalah is used to state that just like Kabbalah the trinity is not a fully pagan idea and has Jewish origin.
This raises the question: if my opponent is arguing that the Trinity is originally a Jewish idea, as he states here and in round 1, then we would like to see a source which unambiguously states that. If Pro can assert this as a fact, then it must be substantiated. Where is the evidence that Jews before the Christian era believed in the Trinity, since Pro seems to take it for granted that this is true? Is there any document or peer-reviewed article or book that says as much? We can accept this statement if Pro is referring to Christianity’s origin as a sect of Judaism, but if Pro is suggesting that Jews before the birth of Christianity believed in the Holy Trinity, we would need to see some proof, any proof, that this is true.

And there are many verses, so the possibility of a trinity is likely. These verses have stumped the rabbis throughout the ages. Their responses were interesting, for example: The angel of the lord is believed to be the metatron by the Rabbis.
Quantity does not equal quality. There is a non-trinitarian explanation for each and every one of the verses you have cited, as I have provided. And what evidence do you have that these verses “stumped” the rabbis? Again, you are only relying on the one example, which doesn’t read to me as “stumped” but as a well-read, if slightly frustrated rabbi offering an alternative explanation to the pedantic Christian.

Because relations between Christians and Jews throughout history were tense. The reason that they don't accept it is because even to this day Jews don't want to identify with Christianity. The trinity is a misunderstood idea and to many Jews it seems pagan.
This doesn’t really concur with what you were saying before. You say that the Trinity was originally a Jewish idea. Now you are saying that the Jews don’t accept the Trinity because they don’t want to identify with Christianity. But why would they identify the Trinity with Christianity if what you are saying, that the Trinity was originally a Jewish idea, is true? If the Jews in the era before Jesus really did believe in the Trinity, as you say, why then did they choose to let go of this belief in particular?

As for the second way, The Jews are humans, they are able to sin and make mistakes and their bias will affect the way they view the bible.
That is very true, and the same is true of Christians. Christians’ bias will affect the way they view the Bible, and there are certain verses in the Old Testament that Christians will point to and argue that the only possible way to interpret them is as a prophecy of Jesus. But while this may seem clear and obvious to Christian believers, their bias may blind them from noticing the other possible interpretations, including that of the people who follow the religious tradition that originally created the Bible. Pro has not cited one verse which points to the Trinity and lacks a coherent non-trinitarian explanation. And as I have hinted at in this round, the idea Pro is proposing, that ancient Jews believed in the Trinity, is quite problematic and raises all sorts of absurdities and impossibilities.
Round 3
Pro
Thank you for your response, Pro. I must start off by pointing out that in Round 2, my opponent has made much use of pointing out that the Hebrew Bible “doesn’t disprove” the notion of the Trinity. That isn’t sufficient. Remember that you are arguing that the Trinity is present in the Hebrew Bible, and the burden of proof is on you to demonstrate this. My job is to demonstrate that these proofs are insufficient and that these verses are talking about things other than the Trinity. Expecting me to find verses that somehow disprove the Trinity is something beyond the scope of the debate.

Uh sir, I have already given you proof with the verses.

As far as I can see, this is a series of unsubstantiated statements. What proof do you have that “Jews became unitarians as a response to Christianity”? When did you state that “rabbis throughout history have wrestled with the concept of the multiple persons of God”, other than one example you gave which was about a completely unrelated topic? We cannot simply make up facts in order to support our worldview without any sources whatsoever.
rabbis wrestling with the trinity:

https://www.sefaria.org/Sanhedrin.38b.19?ven=William_Davidson_Edition_-_English&lang=bi - this Talmudic passage has said that "the lord" referred is angel named Metatron(which is probably the coolest name for angel). Here is what it says:
Rav Naḥman says: This one, i.e., any person, who knows how to respond to the heretics as effectively as Rav Idit should respond to them, but if he does not know, he should not respond to them. The Gemara relates: A certain heretic said to Rav Idit: It is written in the verse concerning God: “And to Moses He said: Come up to the Lord” (Exodus 24:1). The heretic raised a question: It should have stated: Come up to Me. Rav Idit said to him: This term, “the Lord,” in that verse is referring to the angel Metatron, whose name is like the name of his Master, as it is written: “Behold I send an angel before you to keep you in the way and to bring you to the place that I have prepared. Take heed of him and obey his voice; do not defy him; for he will not pardon your transgression, for My name is in him” (Exodus 23:20–21).

https://www.sefaria.org/Sanhedrin.38b.20?ven=William_Davidson_Edition_-_English&lang=bi&with=all&lang2=en The rabbi here is debating with a Christian Jew referred to as "the heretic". Here it goes:

"The heretic said to him: If so, if this angel is equated with God, we should worship him as we worship God. Rav Idit said to him: It is written: “Do not defy [tammer] him,” which alludes to: Do not replace Me [temireni] with him. The heretic said to him: If so, why do I need the clause “For he will not pardon your transgression”? Rav Idit said to him: We believe that we did not accept the angel even as a guide [befarvanka] for the journey, as it is written: “And he said to him: If Your Presence go not with me raise us not up from here” (Exodus 33:15). Moses told God that if God Himself does not accompany the Jewish people they do not want to travel to Eretz Yisrael."
and the next passage:
The Gemara relates: A certain heretic said to Rabbi Yishmael, son of Rabbi Yosei: It is written: “And the Lord rained upon Sodom and upon Gomorrah brimstone and fire from the Lord out of heaven” (Genesis 19:24). The heretic raised the question: It should have stated: From Him out of heaven. A certain launderer said to Rabbi Yishmael: Leave him be; I will respond to him. This is as it is written: “And Lemech said to his wives: Adah and Zillah, hear my voice; wives of Lemech, hearken to my speech” (Genesis 4:23). One can raise the question: It should have been written: My wives, and not: “Wives of Lemech.” Rather, it is the style of the verse to speak in this manner. Here too, it is the style of the verse to speak in this manner. Rabbi Yishmael said to the launderer: From where did you hear this interpretation? The launderer said to him: I heard it at the lecture of Rabbi Meir.
As you can see here, the Jewish Christian says(this and everything here is paraphrased):
In Exodus 24:1). If there was no trinity it should have stated: "Come up to Me."
but the rav said(paraphrased):
The word "lord" here refers to an angel called metatron
but the Christian responded
but if this angel is the lord, then we should worship as the lord
but the rav responded:
You have blasphemed God by replacing him with an angel
But then the Christian says
If so, why do I need the clause “For he will not pardon your transgression”?
the rav then [contradicts himself] says

We did not accept an angel even as a guide. If God did not want us to travel to the land of Israel then we wouldn't
Perhaps Pro was right that we should keep discussion of whether or not the Bible is the word of God out of it. The idea that Isaiah 40:22 (“He stretches out the heavens like a canopy, and spreads them out like a tent to live in”) must refer to the universe’s expansion is incredibly weak. Is that really the only possible interpretation that an educated person would take from this verse? The idea of God “stretching out the heavens like a canopy” over the “circle of the earth” is simply poetic language
It can't be poetic because in most places were the expansion of the universe is mentioned, it also mentioned that God has also made the earth and humans(which is taken literally throughout the bible). So why would you interpret "created the earth" as literal but "expanding the heavens" as poetic and figurative? If we had consistency, we would interpret verses like this as literal.
  
other places were God is mentioned to be expanding heaven:


The word heavens(hebrew shamayim) here means (according to Sefaria - a website for Jewish scriptures):
heaven, heavens, sky
  1. visible heavens, sky
    1. as abode of the stars
    2. as the visible universe, the sky, atmosphere, etc
  2. Heaven (as the abode of God)
This word Shamayim can refer to the visible universe(which is proven to be expanding)

The Strong's Hebrew dictionary states that heaven can mean:
sky or heavens

and indeed the ancient Hebrews thought of Earth as a flat circle and the sky as a dome encasing it
Evidence of this? As far as I know, the Greeks have known the roundness of earth since the 500s bce. 

Also according to the article

and the so-called “deep waters”, the “waters underneath” or, even more dramatically, “the great deep.”
the word for water in hebrew(according to sefaria) can mean
water, waters
  1. water
  2. water of the feet, urine
  3. of danger, violence, transitory things, refreshment (fig.)
So the 3rd definition is literally a synonym for chaos. So we can say that the word here for waters is a synonym for chaos.

Now above the dome, in the “outside” of the dome (who’d say?) you’d find even more water. You guessed it right: those are the “upper waters” and, above them, the “high heaven” or the “heaven of heavens”, where God Himself dwells, as can be seen in the graphic.
However, the verses that say "waters above the firmament, as I have shown above - can be also translated as "the chaos above the firmament"

Also the bible does not mention anywhere that the dome is made of glass - this is made up.

The foundations of the earth are not literal and its mentions are often found in poetic books like the psalms.


With regards to Pro’s response to the three verses we cited proclaiming God’s oneness, Pro seems to think that I meant these verses to debunk the idea of the Trinity. On the contrary, we cited these verses to defend the idea that God’s oneness is an idea that is well-rooted and established in ancient Judaism, rather than a “modern idea” as Pro says. Of course these verses do not “disprove” the Trinity, because the Trinity was not invented as an idea yet. And an atheist would argue that the idea of the Trinity was specifically tailored not to explicitly contradict the Hebrew Bible, since, after all, Christians believe that the God of the Old and New Testaments is one and the same. The idea of the Trinity is famously so complex, God being one and three at the same time, that many believers have trouble wrapping their heads around it. The writers of the Hebrew Bible could not possibly have anticipated this complicated premise in order to denounce it. All this is to say that my job is not to demonstrate that the Hebrew Bible disproves the Trinity, but that it contains no mention of it. Again, the burden of proof is on Pro.

This paragraph is problematic and filled with circular reasoning. Like here:

Of course these verses do not “disprove” the Trinity, because the Trinity was not invented as an idea yet.
You are using your position the idea that we are debating here "because the Trinity was not invented as an idea yet." and applying it to your argument.

The idea of the Trinity is famously so complex, God being one and three at the same time, that many believers have trouble wrapping their heads around it.
Just because its hard to fathom doesn't mean its true.  God is often believed to be on a higher level than us, being able to fully comprehend ideas that would be strange to us(like the trinity).
The writers of the Hebrew Bible could not possibly have anticipated this complicated premise in order to denounce it
of course they wouldn't, and it wasn't their job to do otherwise. The writers of the bible only wrote what God inspired them to write and what has happened in their history.

The chapter you just quoted there is not talking about the messiah. It is one of the four servant songs, each of which is written about an unnamed “servant of Yahweh”, whose identity remains ambiguous and subject to various interpretations. Christians, of course, assume that it is a supernatural prophecy of Jesus. The modern Jewish view is that the “servant” is an allegory for the nation of Israel itself. Some believe that it is indeed referring to the Jewish messiah, or the king Hezekiah. In any case, nowhere in Isaiah 53 is this figure equated with God, and it is completely possible for a political leader to be despised, rejected, and subject to suffering.
Jesus is thought of as a servant of YHWH. This can't be Israel because Israel has sinned against God as said here https://www.sefaria.org/Isaiah.53.4?lang=bi&p2=Ibn_Ezra_on_Isaiah.53.4.4&lang2=bi&w2=all&lang3=en

The modern Jewish view is that the “servant” is an allegory for the nation of Israel itself.
This is not a reliable interpretation because it is modern and was written as a response to Christians. This is the interpretation that I specifically told you to avoid. This can't be Israel because Israel has sinned against God as said here https://www.sefaria.org/Isaiah.53.4?lang=bi&p2=Ibn_Ezra_on_Isaiah.53.4.4&lang2=bi&w2=all&lang3=en

Then we will simply have to agree to disagree. I do not necessarily see how it’s written like a person or acts like a person, except for mild personification in a couple verses. But as I said before, the rabbis maintain that the Spirit is “a quality belonging to God”, so as long as this interpretation remains open, it cannot be said that these verses must refer to the Trinity.
Is there any biblical evidence for this. A quality of a person does not act or speak like a person.

You are the one who said “Talmudic and other rabbinic commentaries are also acceptable sources”.
The Talmudic and rabbinic commentaries are scriptures not traditions

Traditions would be traditional and unwritten beliefs like the thirteen principles of faith

And again, I will reiterate, Dr. Sommer never said that the Trinity is present in the Hebrew Bible, but that the doctrine of the Trinity has interesting connections with Canaanite semi-polytheistic religious traditions that predate Judaism. This is unrelated to the main argument.
He is also the guy who said " I came to my shock when I finished this book is that we Jews have no theological objection to the doctrine of the trinity. I came to the conclusion that we Jews have no theological right to object to the trinity."

This doesn’t really concur with what you were saying before. You say that the Trinity was originally a Jewish idea. Now you are saying that the Jews don’t accept the Trinity because they don’t want to identify with Christianity. But why would they identify the Trinity with Christianity if what you are saying, that the Trinity was originally a Jewish idea, is true? If the Jews in the era before Jesus really did believe in the Trinity, as you say, why then did they choose to let go of this belief in particular?
First of all, I saying that the trinity is an originally Jewish idea has nothing to do with the Jewish acceptance of the trinity just like you said that the kabbalah is not accepted by most Jews. What I said here is that most Jews do not believe the trinity because most of them don't know it is an originally Jewish idea. Jews are humans and like all humans we have gaps in our knowledge.


Basics on the trinity:

  1. There is only 1 God
  2. This God is made up of 3 co-existing, eternal persons which are the father, the son and the holy spirit
  3.  Each person is eternal and uncreated and each one is of infinite power and of infinite knowledge
  4. Each person is fully God
Heresies of the trinity/wrong ways to think of the trinity/Things that the trinity is not:
  1. Modalism - that each person is a form of God, so God would be like superman in were he can change forms.
  2. partialism - that each person is 1/3rd of God 
  3. tritheism - that the 3 persons are 3 separate gods
  4. Arianism - the idea that the son is not fully God
So if the trinity is none of the following is it still logical? The answer is yes but not in a way that we can fathom.

Just because we can't fathom it doesn't mean it is illogical. Take for example a tesseract - which is a 4 dimensional cube. We can't even imagine what a 4 dimensional shape would look like yet it is sound, entirely logical, and may in some sense exist beyond our 3d universe. We can think of the trinity as a tesseract in the sense that there is a higher and lower level. We live on the lower level were beings can only have 1 person and God lives on a higher level were beings can be multipersonal. We beings on the lower level are incapable of comprehending beings on the higher level just like we can't comprehend a 4 dimensional hypershape.
Con
Thank you for your final round, Pro. I will give my last rebuttals before moving on to my concluding statement.

1. Final Rebuttals

In this final round, Pro has relied a lot on simply reiterating his points without addressing my criticisms of them. For example, Pro gave a certain passage from the Talmud that he argued proves the Trinity. I criticized it by saying it doesn’t discount the idea that the angel of the Lord is simply that - an angel. Pro, rather than responded to my criticism, simply linked the same passage again, and copied and pasted its contents without connecting it to any counter-argument.

I will not respond to Pro’s doubling down on the theory that the Bible referring to the “expansion of the heavens” must be interpreted as a miraculous prediction of universal expansion, which means the Bible must be the word of God. I already responded to this claim to my own satisfaction, and Pro failed to acknowledge my challenge that the Quran contains passages that could be similarly interpreted.

Evidence of this? As far as I know, the Greeks have known the roundness of earth since the 500s bce.
I linked evidence for the ancient Hebrew model of the world in the statement you were replying to. Here it is again, and another source too. As for your second statement, you just answered your own question: ancient Greek philosophers had discovered that the world was round, but information was not instantly transferred from civilization to civilization back then. Greece was a whole sea away from the Hebrew world, and there was little contact between the two cultures in the ancient world.

You are using your position the idea that we are debating here "because the Trinity was not invented as an idea yet." and applying it to your argument.
Are you suggesting that because I am stating my opinion, that amounts to circular reasoning? I could point out plenty of examples of my opponent baldly stating his opinion instead of counter-arguments supported by facts or evidence. But I will trust the voters to make this connection on their own. In context, this statement was not meant as a foundation to build my arguments on. I was simply pointing out the absurdity of Pro’s expectancy that I should find a verse that “disproves” the Trinity, and I was giving my perspective on why such a thing probably doesn’t exist. 

This is not a reliable interpretation because it is modern and was written as a response to Christians. This is the interpretation that I specifically told you to avoid.
This is a debate, I’m not sure why my opponent is surprised that I might hold a different view than he does, or follow an interpretation that he “specifically told me to avoid”. Pro can say that Isaiah 53 isn’t talking about Israel all he likes - I have given sources showing that it is the mainstream view of the modern Jewish faith. Pro has made it abundantly clear that he doesn’t like this interpretation, and that’s his prerogative, but he has given us no reason to believe that a Jesus prophecy is the only way of reading this passage, aside from simply stating his personal opinion. And the source he linked is somewhat mystifying, as it doesn’t seem to be saying what he thinks it’s saying at all. Also, it is interesting that my opponent objects when I cite Jewish traditions but freely does it himself.

He is also the guy who said "I came to my shock when I finished this book is that we Jews have no theological objection to the doctrine of the trinity." [sic]
Saying that Jews have no theological objection to the doctrine of the Trinity is a totally different statement from saying the Trinity is present in the Hebrew Bible. Not to mention that this is the opinion of one scholar. Why does my opponent consider Dr. Sommer’s opinion relevant, yet speedily dismisses the work of Maimonides, one of the most respected Jewish scholars of all time?

First of all, I saying that the trinity is an originally Jewish idea has nothing to do with the Jewish acceptance of the trinity…What I said here is that most Jews do not believe the trinity because most of them don't know it is an originally Jewish idea.
My opponent sidestepped a very important question of mine in the final round. From the beginning, he has been urging that “the Trinity is originally a Jewish idea”. Surely if that’s true, at least one Jew had to have accepted it at some point? Or is my opponent proposing that the writers of the Bible came up with the idea of the Trinity without even knowing they had come up with it? Is that even possible? In any case, my opponent reiterated his opinion on modern Jews denying the Trinity and ignored my question, which focused on the ancient Jews. I asked for some evidence that Jews in the ancient world believed in the Trinity, as he has reiterated many times and used as a pillar of his argument. His silence on this question tells us a great deal.

2. Closing Statement

At the beginning of the debate, Pro offered a plethora of Bible verses which, he claimed, proved that the Trinity was present in the Old Testament. I offered explanations for why these verses all have alternative explanations that are in accordance with ancient Hebrew religion at the time the verses were written, and argued that because all of those verses have strong, well-accepted interpretations that have nothing to do with the Trinity, the Trinity cannot be said to be present in the Hebrew Bible. Pro has also asserted on numerous occasions that the Trinity is a Jewish idea. I have asked him for any evidence that this is true, and he has offered none. Pro has also offered up statements by Jewish scholar Dr. Benjamin Sommer and several quotations from the Talmud, but as I have pointed out, none of these sources directly supports his argument, and he failed to tie them into his thesis.

Here is a list of points I have made which my opponent has failed to respond to, or responded in a way that failed to address the point:
1. “Son of God” is used as commonplace language in the Hebrew Bible to refer to humans or angels, and thus does not necessarily imply the Christian doctrine of the Son.
2. “Holy Spirit” is identified by rabbis as a quality of God, not a separate person of God, and thus does not necessarily imply the Christian doctrine of the Holy Spirit. He has stated they are wrong but has given no reasoning for why they are wrong.
3. “Expanding the heavens” is language that is not nearly direct enough to prove that the Bible is referring to universal expansion.
4. The Quran contains very similar verses that can be said to predict the same scientific phenomenon in the same way.
5. I asked my opponent for proof for his statement “Jews became unitarians as a response to Christianity”. He failed to respond.
6. I asked my opponent for proof for his statement “the ancient rabbis all believed that this [Isaiah 53] was about the messiah”. He responded with a source that failed to say anything of the kind.
7. The angel of the Lord referring to itself in the first person could mean that it is a messenger or avatar of God.
8. There exists no evidence that any ancient Hebrews believed in the Trinity.
9. The people composing the Hebrew Bible would have had to believe in the Trinity in order to place the idea into the text.
10. The earliest recorded mentionings of the Trinity took place centuries after the Hebrew Bible was composed.
11. Pro’s argument that his cited verses all point to the existence of the Trinity, with no other possible interpretation, is at odds with the fact that the Jewish faith has completely different interpretations of every verse he has cited, and their interpretations have nothing to do with the Trinity.

From these points alone, which my opponent has failed to respond to, or responded in a way that sidestepped the argument, we can deduce that the verses cited by Pro at the beginning of the debate all have perfectly valid explanations that are in accordance with the society that created them. We can also deduce that it would make more sense for these verses from the Hebrew Bible to accord with the culture and religion for which it was written, rather than the doctrine of a separate religion which emerged centuries later. And so, we cannot accept Pro's argument that the Trinity must be present in the Hebrew Bible.

I will now leave it to the voters to decide whose interpretation is more likely based on the arguments that have been made. Thank you for the debate, Pro, and good luck to you.