Luke 20:41 But he said to them, “How can they say that the Christ is David’s son? 42 For David himself says in the Book of Psalms, “‘The Lord said to my Lord, “Sit at my right hand, 43 until I make your enemies your footstool.”’ 44 David thus calls him Lord, so how is he his son?”
In Luke 20:44, Jesus asks “David thus calls him Lord, so how is he his son?”
His point in asking this question is that the Messiah, who David bowed down to as Lord, was David’s son. In the culture of Jesus time and place, fathers do not bow down to sons. Sons honour their fathers. Jesus threw a bit of a monkey wrench into that when he said that David called his son, even if he was the Messiah, “Lord”. In Jesus’ culture a father did not call the son Lord. The son called the father Lord. Even if the son was the Messiah. The Messiah, after all was just a man especially equipped by God for the saving of Israel, like Moses was. But no one thought that he would expect, or receive, or want – his father to call him “Lord”.
“How can David call his son ‘Lord’”? And no one can answer the question. Because there is only one way. The only way David can call the Messiah Lord is if the Messiah is over him. But David is King of Israel. And there is only one who the king of Israel bows down to at this point in their history – and that is God Himself. We do not know if any of the religious leaders made that connection, but that is the connection Jesus wants them to make.
But it is not just that Jesus is the Messiah and that He is God. There is even more. “There is more?” What more can there be than to say that the Messiah is the eternal Son of God? Isn’t that enough? Of course it is. But it is not where the Bible stops when it talks about the Lordship of the eternal Son of God. Not at all. It says there is more. What the more is what the Messiah did. Messiah/Christ means anointed one. The Messiah is anointed by God to do a work. He is appointed to do something. The Messiah’s work was to save. Every Jew knew that. Every religious Jew believes it still. The Messiah’s work is to come and restore Israel. His work is to come and save Israel from its enemies. He is to come and make Israel what it was originally intended to be. But even that was too small a thing for the Son of God. All who believe are children of Abraham and the Christ came to make children of Abraham from all the people groups of the world. And that is what Psalm 110 is talking about.
Of critical importance to a proper understanding of Psalm 110, is at what time the prophecy of God saying to His Son “Sit here as Lord”, is pointing. God says “Sit here at my right hand until all your enemies are my footstool. What event is this prophecy referring to? We find out in Peter’s Pentecost sermon in Acts 2.
Acts 2:25-36 – For David says concerning him,
” ‘I saw the Lord always before me,
for he is at my right hand that I may not be shaken;
 therefore my heart was glad, and my tongue rejoiced;
my flesh also will dwell in hope.
 For you will not abandon my soul to Hades,
or let your Holy One see corruption.
 You have made known to me the paths of life;
you will make me full of gladness with your presence.’
 “Brothers, I may say to you with confidence about the patriarch David that he both died and was buried, and his tomb is with us to this day.  Being therefore a prophet, and knowing that God had sworn with an oath to him that he would set one of his descendants on his throne,  he foresaw and spoke about the resurrection of the Christ, that he was not abandoned to Hades, nor did his flesh see corruption.  This Jesus God raised up, and of that we all are witnesses.  Being therefore exalted at the right hand of God, and having received from the Father the promise of the Holy Spirit, he has poured out this that you yourselves are seeing and hearing.  For David did not ascend into the heavens, but he himself says,
” ‘The Lord said to my Lord,
Sit at my right hand,
 until I make your enemies your footstool.’
 Let all the house of Israel therefore know for certain that God has made him both Lord and Christ, this Jesus whom you crucified.”
Psalm 110 is about what God says to His Son after the death, resurrection and ascension. The Father says Psalm 110:1 to the Son as a result of His obedience in going to the cross, purchasing back His people from hell, triumphing over death itself. What Psalm 110 is doing for us is allowing us a peak into the very council chamber of the eternal trinity and hearing part of the plan of salvation being articulated.
David doesn’t just call Jesus Messiah because He is going to save. He calls Jesus Messiah because He saves through dying and rising from the dead. He defeats the final and most powerful enemy. He rises from the dead and guarantees that all who are in Him will rise from the dead as well. And because of this mind bogglingly great work, God instills Jesus as King over all. Did David know this? When he sat down to write this poem and God put it into his head to write these words, did he know he was talking about the second person of the trinity who would come to earth and live a sinless life and die in the place of His people and rise victorious over sin and hell and death? I have no idea. I doubt it. But it is what the Psalm is about. And it is what Jesus wanted the Sadducees and Pharisees that day to start putting together. And it is what we need to know and love if we are going to honour Jesus Christ as our Lord.
Wasn’t Jesus Lord before the resurrection? Yes. Wasn’t Jesus the Messiah before the resurrection? Yes, of course He was. But when He completed the work He came to do; when he rose from the dead and fully purchased His people and guaranteed their eternal life; when His work was done and He went back to glory, God rewarded Him. And He became Lord as a reward for what He had accomplished. He became Messiah not just as the anointed One but as the reigning King. See what Peter says. Why does the Father say to the Son “Sit here …”? He says it to Him because the Son has defeated death. See Phil. 2:6-9. See I Corinthians 15:20-27a.
Jesus is Lord because God has highly exalted Him to His own right hand because of His death and resurrection. Lord then means reigning King. It means Sovereign Ruler over all that it. It means Jesus has absolute power, control and reign. This is our Saviour. This is the One we call “friend”. This is the One who never leaves us or forsakes us. This is the One who we go to with all our problems, big and small. And this is the one who loves to have us come. Too many Christians still have a Jesus who walks around Galilee, who comes upon them and discovers what is wrong and fixes it. But the wonder of the church’s relationship with Jesus is not that we go to the God Man in His humility and humanity. The wonder of it is that we can go to Him now that He reigns as the uncontested, uncontestable Ruler of everything. He has purchased us by His own blood and now He allows us to call on Him. He allows us to serve Him. He allows us to ask favours of Him. He allows us to worship and sing and pray and speak of Him to others.
There is not a Prime Minister, President, King, Queen, dictator, despot or leader of any kind who would trust me with delivering their coffee. But the One before whom they will all bow one day, says that I am His co-heir, friend, and servant. Bow indeed. How can we who know Him do anything less? This is a stunning reality that brings us to an eternity of joyful worship.