The religious and political leaders of Israel wanted to arrest and put Jesus to death. It was the popularity of Jesus as a prophet among the people that prohibited them from openly laying hands on Him (Mat 21:46, 26:3-5). In order to diminish His popularity, Israel’s leaders tested Jesus with “trick” questions hoping to lead Him to give unpopular answers (Mat 22:15-40). Instead, Jesus answered in such a way as to amaze the people and silence His enemies.
After the last group of leaders, the Pharisees, had taken their best shot, Jesus asked them questions which went to the heart of the matter (Mat 22:41-46). “What do you think about the Christ?” “Whose Son is He?” They gave the correct answer to the second question, “The Son of David.” The chief priest and scribes had become indignant on Palm Sunday when the children in the temple cried out, “Hosanna to the Son of David!” Jesus was addressed as the Messiah, and the leaders became angry.
Jesus is the Son of David, but He is more. Jesus then quoted from Psalm 110 of which David is the author. “The LORD said to my Lord, ‘Sit at My right hand, till I make Your enemies Your footstool.’” The One David called “my Lord” is the Messiah or the Christ. Jesus followed up with a question they were not able to answer, “If David then calls Him ‘Lord,’ how is He his Son?” A father would not call his son, Lord! The Christ is more than a man, and greater than David who called Him, Lord. Jesus is God Incarnate. He is the Son of David, but He is also the Son of God! Paul wrote in Romans 1:3-4,

…concerning His Son Jesus Christ our Lord, who was born of the seed of David according to the flesh, 4 and declared to be the Son of God with power according to the Spirit of holiness, by the resurrection from the dead.