Luke 20:44

David in truth was both the Father and the servant of Christ, the former indeed according to the flesh, the latter in the Spirit.

Therefore He asks the question, and having excited their doubts, leaves them to deduce the consequence; as it follows, David therefore calleth him Lord, how is he then his son?

We must believe then that Christ is both God and man, and that His enemies are made subject to Him by the Father, not through the weakness of His power, but through the unity of their nature, since in the one the other works. For the Son also subjects enemies to the Father, in that He glorifies the Father upon earth. (John 17:6.)

Or, that He sits on the Father's right hand proves His heavenly glory. For whose throne is equal, their Majesty is equal. But sitting when it is said of God signifies a universal kingdom and power. Therefore He sitteth at the right hand of the Father, because the Word proceeding from the substance of the Father, being made flesh, putteth not off His divine glory. We then likewise in answer to the new Pharisees, who neither confess the Son of the holy Virgin to be the true Son of God, nor to be God, but divide one son into two, put the like objections: How then is the Son of David David's Lord, and that not by human lordship, but divine?

And since they had been defeated in argument, they ask Him no further questions, but seize Him, and deliver Him up to the Roman power. From which we may learn, that the poison of envy may indeed be subdued, but it is a hard thing to keep it at rest.