Here is the Greek text:
εἶπεν αὐτοῖς Ἰησοῦς, Ἀμὴν ἀμὴν λέγω ὑμῖν, πρὶν Ἀβραὰμ γενέσθαι ἐγὼ εἰμί.
Followed by the English translation (ESV): “Jesus said to them, ‘Truly, truly, I say to you, before Abraham was, I am.”
The New World translation has this: “Jesus said to them: ‘Most truly, I say to you, Before Abraham came into existence, I have been.'” The Watchtower organization has argued that there is no relation at all of this verse to the famous “I am that I am” of Exodus 3:14. But there are several points to notice here which they do not address in any way, shape, or form. First of all, the tense of their translation is completely and utterly wrong. If John had wanted to say that Jesus existed before Abraham did in the past (but not including any idea of eternal pre-existence), without any confusion on the score, he had no fewer than three tenses at his disposal: aorist, imperfect, or perfect. The NWT reflects what would be a perfect tense. The Greek is PRESENT TENSE. It indicates ongoing existence before Abraham was. God does not exist in time the same way that we do. God is both transcendant and immanent in time. The way to express this is to say that in the past God is (present tense). The NWT translators knew this, which is why they completely changed the meaning into something finite.
The second point that they do not engage at all is the fact that what Jesus says here mirrors Exodus 3:14 ***precisely*** in the Greek translation of the OT (called the Septuagint, or LXX for short). They Watchtower people offer *zero* argumentation for why there is no connection, especially given the exact Greek correspondence between the two verses. I should mention that it is the first two words of the Greek in God’s words in Exodus 3:14 which I am talking about. The Watchtower people also fail utterly in their explanation of why the people picked up stones to stone Him. That happens when someone is uttering blasphemy. Jesus could have corrected their misunderstanding of His actions if He wasn’t claiming divinity. No, it is because He *was* claiming divinity that they picked up stones to stone Him.