What does Luke 20:37 mean?
The Sadducees are trying to disprove Jesus' teaching about the resurrection of the dead. They use a law in the Torah—which they deeply value—to show the Mosaic law is incompatible with resurrection. The Sadducees did not believe in resurrection of the dead or any type of afterlife. If the resurrection is not true, then Jesus' ministry, which is largely based on the call to repent and avoid God's judgment, can be called into question. And the people who are crowding around Him on the Temple Mount, listening to His teaching, should go back to following the Sadducees, instead (Luke 20:27–33).Jesus is referring to Exodus 3:6. Moses had been keeping the sheep of his father-in-law and saw a bush that was on fire but not consumed. The angel of the Lord inside the bush revealed Himself as "the God of Abraham, the God of Isaac, and the God of Jacob." This is not the clearest Old Testament text about the resurrection of the dead. That would be Daniel 12:2: "And many of those who sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt." But the Sadducees are defined by their love of the Torah—the first five books of the Scriptures—which Moses wrote and which includes the book of Exodus. They dismiss the importance of texts such as those of Daniel. As with the chief priests, scribes, and elders (Luke 20:1–8), Jesus uses what these religious leaders claim to believe to uncover their own hypocrisy.
The inclusion of Abraham, Isaac, and Jacob isn't meant to just list off the significant patriarchs. These are the men to whom God gave His covenant (Genesis 12:1–3; 15:1–21; 26:1–5; 28:13–15), but they did not see its fulfillment (Hebrews 11:13–21). If they have not experienced the fulfillment of God's promises, they cannot remain dead. "Now he is not God of the dead, but of the living, for all live to him" (Luke 20:38).