Jesus- David’s son or David’s Lord?

Luke 20:41-44  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?”

 J.C.Ryle comments:

Let us observe in this passage, what striking testimony to Christ’s divinity the book of Psalms contains. We read that after patiently replying to the attacks of His enemies, our Lord in turn propounds a question to them. He asks them to explain an expression in the hundred and tenth Psalm, where David speaks of the Messiah as his Lord. To this question the Scribes could find no answer. They did not see the mighty truth, that Messiah was to be God as well as man, and that while as man He was to be David’s son, as God He was to be David’s Lord. Their ignorance of Scripture was thus exposed before all the people. Professing themselves to be instructors of others and possessors of the key of knowledge, they were proved unable to explain what their own Scriptures contained. We may well believe that of all the defeats which our Lord’s malicious enemies met with, none galled them more than this. Nothing so abashes the pride of man, as to be publicly proved ignorant of that which he fancies is his own peculiar department of knowledge.

We have probably little idea how much deep truth is contained in the book of Psalms. No part of the Bible perhaps is better known in the letter, and none so little understood in the spirit. We err greatly if we suppose that it is nothing but a record of David’s feelings, of David’s experience, David’s praises, and David’s prayers. The hand that held the pen was generally David’s. But the subject matter was often something far deeper and higher than the history of the son of Jesse.

The book of Psalms, in a word, is a book full of Christ–Christ suffering–Christ in humiliation–Christ dying–Christ rising again–Christ coming the second time–Christ reigning over all. Both the advents are here–the advent in suffering to bear the cross–the advent in power to wear the crown. Both the kingdoms are here–the kingdom of grace, during which the elect are gathered–the kingdom of glory, when every tongue shall confess that Jesus is Lord. Let us always read the Psalms with a peculiar reverence. Let us say to ourselves as we read, “A greater than David is here.”

The remark now made, applies more or less to all the Bible. There is a fullness about the whole Book, which is a strong proof of its inspiration. The more we read it, the more it will seem to contain. All other books become threadbare, if they are constantly read. Their weak points, and their shallowness become every year more apparent. The Bible alone seems broader, and deeper, and fuller, the oftener it is studied. We have no need to look for allegorical and mystical meanings. The fresh truths that will constantly spring up before our eyes, are simple, plain, and clear. Of such truths the Bible is an inexhaustible mine. Nothing can account for this, but the great fact, that the Bible is the word, not of man, but of God.