Your father Abraham rejoiced to see my day: and he saw it, and was glad. Jesus speaking

Then said the Jews unto him, Thou art not yet fifty years old, and hast thou seen Abraham? Abraham lived apx 1800 years before them

Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am. 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. John 8:58 KJV

The Jews realized that Jesus had just said he was not only preexistent but selfexistent or JEHOVAH (I AM). Jesus and Jehovah are the same person (i.e. GOD)!