While the Pharisees were gathered together, Jesus asked them a question, saying, "What do you think of the Christ? Whose son is he?" They said to him, "The son of David." He said to them, "How is it then that David, inspired by the Spirit, calls him Lord, saying, 'The Lord said to my Lord, Sit at my right hand, till I put thy enemies under thy feet'? If David thus calls him Lord, how is he his son?" And no one was able to answer him a word, nor from that day did any one dare to ask him any more questions. Matt. 22:41-46, RV.
Here we have an argument that most modern Christians do not fully understand. But that was not so for the Jews of Jesus' day. We need to spend some time examining the issues He raised in this passage--issues central to the rest of the New Testament.
The first thing we should note is that Jesus' question regarding His identity is the same one He had brought up privately with the disciples on the road to Caesarea Philippi, when He asked them "Whom do man say that I am?" (Mark 8:27). Peter's answer was that Jesus is the Christ. And from that time forward Jesus began to explain to His disciples what it meant to be the Christ.
In Matthew 22 He moves from unfolding the significance of the Christ from the disciples to the Pharisees. But with them Jesus probes into "the Christ" and His relationship to David. To understand the passage it is important to remember that the Jews did not use Christ as a name but rather as a position. Thus Jesus framed His question in terms of "the Christ."
A second term that we need to understand is "son of David." Of all the titles for the Christ the most common was son of David. The Jews looked forward to a Messiah of the warrior-king type modeled by David. In that context, after the Pharisees publicly identified identified the Christ as the son of David, Jesus asked His most important and perceptive question: "How is it then that David, inspired by the Spirit, calls him Lord...?"
Here Jesus had the Pharisees on the spot. His use of Psalm 110, which all agreed was Messianic, threw them into confusion, since in that passage David calls the Messiah his "Lord," the very word used in the Greek version of the Old Testament to translate Yahweh or God. The Pharisees recognized at this point that the Christ would not merely be David's son, but his divine Lord.
And with that, they realized that Jesus had bested them in their knowledge of the Bible. As a result, they feared to ask Him any more questions.