Luke 20:37
But in the account of the burning bush, even Moses showed that the dead rise, for he calls the Lord the God of Abraham, and the God of Isaac, and the God of Jacob — Moses showed that the dead rise: the proof from the Torah that the Sadducees accept. The burning bush account (Exodus 3:6) has God self-identifying as the God of Abraham, Isaac, and Jacob — present tense, at a time when the patriarchs had been dead for centuries.