If David … Son? The argument is this: David speaks with highest reverence of Messiah, calling him his Lord: how is this attitude consistent with the fact that Messiah is David's Son? How can Messiah be both Son and Lord of David?
We, who have learned the truth concerning the two natures of Christ, can readily answer the question. He is both "the Root and the Offspring of David" (Revelation 22:16). The Athanasian Creed offers the required solution of the seeming paradox: "God, of the substance of the Father, begotten before the worlds; and Man of the substance of his mother, born in the world; perfect God, and perfect Man … who although he be God and Man, yet he is not two, but one Christ."
Here was an explanation (if the Pharisees took his words to heart) of much that had excited their indignation, and caused cavil and carping. He claimed to be the Messiah; and Messiah, as Scripture presented him, had a twofold nature.
When, therefore, he asserted equality with the Father when he, "being man, made himself God" (John 10:33), he was vindicating that Divine nature which he as Messiah possessed. Jesus did not further elucidate this mystery.
He had given food for reflection; he had unfolded the hidden meaning of Scripture; he had shown the shallowness of the popular exegesis; the knowledge was here; there was wanting only the will to raise the flower of faith in the heart of these obdurate hearers.