What is the meaning of Matthew 22:41-46?

41 While the Pharisees were gathered together, Jesus asked them, 42 Saying, What think ye of Christ? whose son is he? They say unto him, The Son of David. 43 He saith unto them, How then doth David in spirit call him Lord, saying, 44 The LORD said unto my Lord, Sit thou on my right hand, till I make thine enemies thy footstool? 45 If David then call him Lord, how is he his son? 46 And no man was able to answer him a word, neither durst any man from that day forth ask him any more questions. (Matthew 22:41-46 KJV)

William Burkitt’s Commentary

The Pharisees had often put forth several questions maliciously unto Christ, and now Christ puts forth one question innocently unto them; namely, What the thought of the Messiah whom they expected? They reply, that he was to be The son of David, a secular prince descending from David, that should deliver them from the power of the Romans, and restore them to their civil rights. This was the notion they had of the Messiah, that he should be a man, the Son of David, and nothing more.

Our Saviour replies, Whence is it then that David calls the Messiah Lord? The Lord said unto my Lord Ps 110:1 how could he be both David’s Lord, and David’s son? No son is lord to his father; therefore if Christ were David’s sovereign, he must be more than man, more than David’s son. As man, so he was David’s son; as god-man, so he was David’s Lord.

Note hence, That although Christ was truly and really man, yet he was more than a bare man: he was Lord unto, and was the salvation of his own forefathers.

Note, 2. That the only way to reconcile the scriptures which speak concerning Christ, is to believe and acknowledge him to be God and man in one person. The Messiah, as a man, was to come forth out of David’s loins; but as a god-man, he was David’s sovereign and Saviour. As man, he was his father’s son; as God, he was Lord to his own father.