"Teacher, Moses wrote for us that if a man's brother dies , leaves his wife behind, and leaves no child, his brother should take the wife and produce offspring for his brother.
References for Mark 12:19
There were seven brothers. The first took a wife, and dying, left no offspring.
The second also took her, and he died, leaving no offspring. And the third likewise.
The seven also left no offspring. Last of all, the woman died too.
References for Mark 12:22
In the resurrection, when they rise, whose wife will she be, since the seven had married her?"
References for Mark 12:23
Jesus told them, "Are you not deceived because you don't know the Scriptures or the power of God?
For when they rise from the dead, they neither marry nor are given in marriage but are like angels in heaven.
Now concerning the dead being raised-haven't you read in the book of Moses, in the passage about the burning bush, how God spoke to him: I am the God of Abraham and the God of Isaac and the God of Jacob ?
References for Mark 12:26
He is not God of the dead but of the living. You are badly deceived."
One of the scribes approached. When he heard them debating and saw that Jesus answered them well, he asked Him, "Which commandment is the most important of all?"
References for Mark 12:28
"This is the most important," Jesus answered: Listen, Israel! The Lord our God, the Lord is One.
References for Mark 12:29