Mark 12:26 And as touching the dead, that they rise: have ye not read in the book of Moses, how in the bush God spake unto him, saying, I am the God of Abraham, and the God of Isaac, and the God of Jacob?
The Saducees wanted to place Jesus where he could not answer their foolish question. They did not believe in the resurrection of the dead. He reminds them of scripture. I love him doing that, for it proves without a doubt that the word written is the truth. This was the account of Moses hearing from God in the burning bush. Was God in the bush?
Exo 3:2 And the angel of the LORD appeared unto him in a flame of fire out of the midst of a bush: and he looked, and, behold, the bush burned with fire, and the bush was not consumed.
An angel was in the bush, but, and this is important: Angels only hear from God and are his messengers. (Do not pray to an angel of God, they only hear and obey God.) So it was God speaking in the bush through an angel messenger.
The message: I Am, the name of God, I am the God of Abraham, Isaac and Jacob. They were living souls.
Mark 12:27 He is not the God of the dead, but the God of the living: ye therefore do greatly err.
One final word. If the angels speak for God, why not men who hear from the Holy Spirit? The prophets, Moses and Holy men of God, also heard from God and wrote his message in the Bible. The Bible is God breathed, the inspired word of God. It is the living word from our Living God and our Living savior.
John 11:25 Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live:
John 11:26 And whosoever liveth and believeth in me shall never die. Believest thou this?
The I am again. Jesus is the resurrection and the life. Jesus is God the Son. I believe.