Mark 12:27

He is not the God of the dead Our Lord thus taught them that the words implied far more than that God was the God, in Whom Abraham and the patriarchs trusted and worshipped.

but the God of the living Jehovah could not have called Himself the God of persons who do not exist, and over whom death had completely triumphed. The patriarchs, therefore, though their bodies were dead, must themselves have been still living in the separate state, and awaiting the resurrection.