The Abraham Allegory shows that when God changed Abram's name to Abraham, it was really a deeper picture of God changing His own Old Covenant name , Jehovah, to the New Covenant name of Jesus. God tells us in Galatians that Sarah is a picture of the New Covenant. She is also a picture of the New Jerusalem which is The Church which is the Bride of Christ. This name change is also how Jesus defeated the Devil. Don't you remember that famous portion of the Bible in Isaiah that says of Jesus "and He shall be called Wonderful, Counselor, The Mighty God, The Everlasting Father, The Prince of Peace?" Now it all makes sense. Jesus is the Great I AM, God manifest in the flesh.