This question finishes what Luke 20:41 began. A father does not call his own descendant "Lord." Yet David, speaking of the Christ, says "my Lord." Jesus sets the two facts side by side and asks how both can be true. Gill puts the question plainly: "in what sense can he be both his Lord and son?" Jesus is not trying to trap anyone. He is pushing His hearers past the answer they already had toward the answer they needed.

Luke records no reply. Just before this, the leaders "durst not ask him any question at all" (Luke 20:40). Matthew adds that "no man was able to answer him a word" (Matthew 22:46), and Mark notes that "the common people heard him gladly" (Mark 12:37). In Luke, Jesus turns to His disciples, in the hearing of all the people, and warns them, "Beware of the scribes" (Luke 20:45-46).

In Psalms 110:1 the first "LORD" (in capitals in the KJV) stands for God's covenant name, and "my Lord" is the one David honors as his master. Gill reads the Psalm as "a speech of God the Father to his son Jesus Christ." The Greek of Luke 20:44 uses kurios (Lord) and huios (son), placing the two titles in the same short sentence.

Here Jesus shows that the Christ is more than a great king from David's family. Matthew Henry answers the puzzle this way: "Christ, as God, was David's Lord, but Christ, as man, was David's Son." Barnes says there is no way of answering the question "but by the admission that the Messiah was divine as well as human."

The Psalm also looks ahead. The one David calls Lord is told to sit at God's right hand until his enemies are made his footstool. After the resurrection, Peter used this same verse to proclaim that God "hath made that same Jesus, whom ye have crucified, both Lord and Christ" (Acts 2:34-36). The question the scribes could not answer, the empty tomb did.