Jesus says He is God.

John 8.58 Jesus answered, "The truth is, I existed before Abraham was even born!" or "Truly, truly, before Abraham was, I am."

"Your ancestor Abraham rejoiced as he looked forward to my coming. He saw it and was glad" (v.56).

Observe the holy name of God - I AM in Exodus 3.14: God said to Moses, "I AM WHO I AM." And he said, "Say this to the people of Israel, 'I AM has sent me to you.'"
After Jesus said He was God, "Then took they up stones to cast at him: but Jesus hid himself, and went out of the temple, going through the midst of them, and so passed by" (v.59). According to Lev. 24.16, the law required the religious leaders put Jesus to death if He was falsely claiming to be God and because they did not believe He was the one Abraham spoke of, they attempted to cast stones upon him. "And he that blasphemeth the name of the LORD, he shall surely be put to death, [and] all the congregation shall certainly stone him: as well the stranger, as he that is born in the land, when he blasphemeth the name [of the LORD], shall be put to death" (Lev. 24.16).

Why would the religious leaders of Israel, or today throughout the world, wish to put Jesus to death if Jesus was not claiming to be God? He would in fact just be a lunatic, and of no threat whatsoever, needing hospitalization. But because He is a threat to the beliefs of man, men seek His death, for man is to selfish to place himself underneath God Almighty his Creator.