Jesus is coming right out with it: “I’m God. Deal with it. And make whatever changes in life are required to acknowledge that truth.”
He had just entered Jerusalem with Messianic fulfillment as the King who comes in the name of the Lord (Ps. 118.26). Then he enters the Temple with Messianic fulfillment, chasing out the moneychangers, and declaring himself to be the Messiah from God, purging his Father’s house (Mal. 3.1). The leaders don’t deny his right to do so if he will only support his claim. Jesus tells a parable, identifying the vineyard owner as God Himself, and himself as the beloved Son. He claims that he is the Messianic fulfillment of Ps. 118.22: the rejected stone who is really the focal point of it all. Therefore they need to give God what rightly belongs to God (Lk. 20.25), and recognize that eternity is coming when all will stand before God (Lk. 20.38).
Jesus keeps the pressure on. It is just a few days until he dies, so it’s a full-court press to make himself known. He initiates the conversation this time, with the age-old question: How can God have a son? It’s the question that plagues both Jews and Muslims, Jehovah’s Witnesses, Unitarians, and, frankly, it’s a question that haunts many people: How can God be one and more than one at the same time?
In “Knowing God” by J.I. Packer, he says that it’s not the atonement, resurrection, virgin birth, or the miracles that provide the stumbling block to people, but the incarnation. How can God be a person, and be separate but the same from God in heaven? How can Jesus be both God and man? And if one can answer that question, then the virgin birth, miracles, atonement, and resurrection are easy. Jesus hits it head on: How can the Messiah be the son of David? (Or, how can God be man?)
Jesus quotes David, whom they all admitted wrote the words of God himself. In the Psalm (110.1), David heard YHWH speaking to the Messiah and calling him “Lord.” The Messiah, David claims, is equal to God (sits on right hand, sovereign over all), and yet is a man (a son of David)—human and God at the same time, sharing the nature of both. And this Messiah, continues David, will be a priest and a king. The resurrection, Jesus asserts, will be what affirms the claim. Everything will hang on the resurrection. If he comes back, that means he conquered death, something only God can do, verifying his declaration.
I guess the point is this: for Jesus’ audience (and many readers since), Jesus was saying it’s theologically possible for God to be a singularity and a plurality at the same time. It’s Old Testament and New Testament. The more precise point is the implications. If Jesus is God, this isn’t just religion, opinion, or one of the choices of how to spend one’s life; nor are indifference or avoidance by denial. Truth demands a hearing, and one neglects it to his or her own peril.