How does John 8:58 prove that Jesus is the Jehovah of the Old Testament?
In John 8:58 Jesus says, 'Before Abraham was, I am,' echoing the burning bush where God told Moses, 'I am that I am.' That self-designation identified Jehovah. Jesus was therefore claiming to be the same one who spoke from the bush—the Jehovah of the Old Testament.
Les teaches that in John chapter 8 the Pharisees confronted Jesus, saying He was not even fifty years old and yet claimed to have seen Abraham; they asked, 'Who are you anyway?' Jesus answered, 'Before Abraham was, I am.' Les explains that Jesus was telling them, 'I'm the same one that spoke from the burning bush. I'm the Jehovah of the Old Testament.' This connects back to Exodus, where the voice from the burning bush told Moses to tell Israel that 'I am that I am' had sent him. The same Jehovah later identified Himself to Paul as Jesus, showing Jesus is the God of Abraham, Isaac, and Jacob.
Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am.
And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you.