As Jesus taught in the temple he asked this question. “How can the scribes say that the Christ is the son of David?” (Verse 35) He continued on showing that, “David himself, inspired by the Holy Spirit, declared, ‘The Lord said to my Lord, Sit at my right hand, till I put thy enemies under thy feet.’ David himself calls him Lord; so how is he his son?” (Verse 36-37)
It’s a good point. The scribes and Pharisees were looking for the Christ to come and give the salvation prophesied in the Old Testament. However they were looking for an earthly king. The Son of David they expected to be a king of the lineage of David who was king over all of Israel in this world.
But they did not recognise Jesus as the king they were looking for. As far as they were concerned he was just the son of a carpenter, and from a ministry perspective, something of a thorn in their side. He preached the truth and it was clear to all, including some of the scribes and Pharisees, that he was from God for the signs he performed bore witness to the teachings he gave.
They were looking for a leader and a king to take them out of the oppression of the Roman empire and restore the former glory of the nation of Israel. However Jesus came to bring a new teaching and a New Covenant that would establish the nation of Israel, not in a physical way, but in the spirit. The spiritual Israel would be composed of many peoples, nations and tongues, not based upon bodily descent from Abraham, Isaac and Jacob, but based upon the faith of those three patriarchs.
It is the children who share the faith of Abraham who are the children of the spiritual Israel. And Jesus is the king of that nation in the kingdom of God.
David the king recognised this coming kingdom, which is why he called the Christ his Lord. It had been revealed to David that the Christ would be descended from his line, but that he would also be the Son of God. The scribes were looking for a physical king, not a spiritual kingdom. They were looking towards the power and glory of a worldly kingdom rather than the glory of God’s kingdom in the spirit. As a consequence of their blindness, they missed the Christ when he appeared. Their loss though is our gain for through Jesus we have access to the Spirit and the kingdom of God.