What does Matthew 22:45 mean?
The Pharisees who have been challenging Jesus have seen the tables turned. He has asked them to identify whose son the Christ is. They answer as all good Jewish people would: that the Christ, the Messiah, is the son of David. It is clear from the Old Testament Scriptures that the Messiah would be a descendant of King David, the great king from Israel's golden age (Matthew 22:41–44).Jesus, though, has pushed back with a hard question. If the Christ is David's descendant, why in Psalm 110:1 does David call the Christ "my Lord"? Why would anyone describe their "son" as "my Lord"?
The answer, of course, was that the Messiah would not only be a descendant of David but would also be the Son of God, making Him both David's son and Lord. The fact that Jesus is Messiah as well as the Son of God, making Him divine, is a truth the Pharisees and other religious leaders will willfully miss. It is a cornerstone in their commitment to condemn Him for blasphemy.