John 8:58 is not a teaching on the trinity or that we should believe or confess that Jesus is God. "I am" was a common phrase and it isn't the name of anyone. At the last super, the disciples were trying to find out who would deny the Christ. They said literally, "Not I am, Lord" Matthew 26:22, 25. No one would say the disciples were trying to deny they were God because they were using the phrase "Not I am." "I am" was a common way of designating one self and it did not mean you were claiming to be God. The argument is made that because Jesus was "before" Abraham, Jesus must be God. Jesus figuratively existed in Abraham's time. He did not actually physically exist as a person, but rather he existed in the mind of God as God's plan for the redemption of man. In order for the Trinitariana rgument that Jesus' "I am" statement in John 8:58 makes him God, his statement must be equivalent with God's "I am" statement in Exodus 3:14. The two statements are very different. The Greek phrase in John does mean "I am." The Hebrew phrase in Exodus means "to be" or "to become." God was saying "I will be what I will be."