The same day the Sadducees, who say there is no resurrection, came to Him and asked Him, 24 saying: “Teacher, Moses said that if a man dies, having no children, his brother shall marry his wife and raise up offspring for his brother. 25 Now there were with us seven brothers. The first died after he had married, and having no offspring, left his wife to his brother. 26 Likewise the second also, and the third, even to the seventh. 27 Last of all the woman died also. 28 Therefore, in the resurrection, whose wife of the seven will she be? For they all had her.”
29 Jesus answered and said to them, “You are mistaken, not knowing the Scriptures nor the power of God. 30 For in the resurrection they neither marry nor are given in marriage, but are like angels of God in heaven. 31 But concerning the resurrection of the dead, have you not read what was spoken to you by God, saying, 32 ‘I am the God of Abraham, the God of Isaac, and the God of Jacob’? God is not the God of the dead, but of the living.” 33 And when the multitudes heard this, they were astonished at His teaching. — Matthew 22:23-33.
Note: “have you not read” (vv.31,32). — Jesus quotes from the Pentateuch (Exodus 3:6), a portion of Scripture particularly valued by the Sadducees. That God “is” (not “was”) the God of the patriarchs proclaims the resurrection because “He is not God of the dead, but of the living.” The eternal God calls His saints to an eternal relationship with Himself. All this implies that the patriarchs continue to live and will be resurrected in the future.