One, evidently a Unitarian who does not believe in the prehuman existence of Jesus, has presented the idea that the Greek phrase in John 8:58, often transliterated as “prin Abraam genesthai ego eimi”, should be rendered as “before Abraham was God”. This is based on the assumption that “ego eimi” is being used in John 8:58 as the name often transliterated as EHJEH (from the Masoretic text) in Exodus 3:14.
We have no scriptural reason to think that when Jesus spoke the words often transliterated as EGO EIMI in John 8:58, that he was using the Holy Name EHJEH of Exodus 3:14. Jesus was responding to the Jews' question regarding his age, stating that he, himself, had been in existence before Abraham. They did not ask if God existed before Abraham, for I am sure that they already knew that God existed before Abraham.
It was claimed that John 8:58 should be rendered as “God (Ehyeh) was before Abraham”, because “Yeshua's life started when he was born on earth, as you can see in Luke 2:52”. Of course, there is nothing in Luke 2:52 that says that Jesus did not have a life in heaven with his God before he was made flesh, so the idea has to assumed, added to, and read into what is stated in that verse.
The problem would be with the Greek application of the Greek verb often transliterated as “genesthai”, which is rendered as “was” in the rendering “Before Abraham was God”. This rendering would make the subject of genesthai to be “EGO EIMI”. Evidently, such an application of “EGO EIMI” is that with the thought that Ego Eimi is a name, and thus is used as a noun, and as the subject of genesthai. Evidently, this is thought to correspond with the way the third usage of EHJEH in Exodus 3:14 is used as a noun, designating the first-person verb form of God's Holy Name, which is presented in the third-person verb form, often rendered into English as “Jehovah” or “Yahweh”, in Exodus 3:15.
We do not know of any usage of Ego Eimi in the manner anywhere in the Greek NT, or even in the LXX of the Old Testament, that does such with the Greek phrase EGO EIMI.
In the Bible, Hebrew names from the Old Testament are usually translated, but the sound of the Hebrew is adapted and given a Greek form. If Jesus had intended to use the Holy Name of Exodus 3:14, it would have been extraordinary for him to not bring that name into Greek, adapted from the Hebrew sounding of that name.
Another problem is with the word genesthai. Unlike EIMI, which pertains to being or existence, genesthai, carries with it a meaning of coming into existence. To use EGO EIMI as the subject of genesthai would make Jesus' God appear to have come into existence before Abraham.
I put the given rendering into Google's AI, and got the following results:
No, the Greek phrase "EGO EIMI" cannot be used as a noun and the subject of the Greek word "genesthai" in John 8:58.
Here is a grammatical breakdown of the relevant part of the Greek text (πρὶν Ἀβραὰμ γενέσθαι, ἐγὼ εἰμί - prin Abraam genesthai, ego eimi):
prin: This is an adverb/conjunction meaning "before".
Abraam: This is the noun "Abraham", in the accusative case, which functions as the subject of the following infinitive genesthai in this construction.
genesthai: This is an aorist infinitive verb, meaning "to become", "to come into being", "to be born", or "to arise". In this context, it refers to Abraham's birth or existence. The subject of an infinitive in Greek typically appears in the accusative case.
ego eimi: This is a complete clause on its own.
ego: This is the first-person singular personal pronoun, meaning "I". It is the subject of eimi.
eimi: This is the first-person singular present active indicative form of the verb "to be", meaning "I am", "I exist", or "I live".
The phrase "EGO EIMI" functions as the main verb and its subject in the independent clause, while the entire phrase "prin Abraam genesthai" functions as an adverbial clause modifying the main clause, indicating the time of the action (before Abraham was born). "Abraam" is the subject of genesthai.
Therefore, "EGO EIMI" is not a noun, nor is it the subject of genesthai. The structure of the sentence means: "Before Abraham came into being, I exist" (or "I have been in existence").
Nevertheless, Jesus' statement that his God and Father was in existence before Abraham does indeed not answer the question, “You are not yet fifty years old! Have you seen Abraham?”. -- John 8:57.