John Calvin Commentary Psalms 89:3

"I have made a covenant with my chosen, I have sworn unto David my servant:" — Psalms 89:3 (ASV)

I have made a covenant with my chosen. To more effectively confirm himself and all the godly in the faith of the Divine promise, he introduces God Himself as speaking and sanctioning, by His authority, what had been said in the preceding verse. As faith ought to depend on the Divine promise, this manner of speaking, by which God is represented as coming forward and drawing us to Himself by His own voice, is more powerful than if the prophet himself had simply stated the fact.

And when God in this way approaches us first, we cannot be charged with rashness in coming confidently to Him; just as, on the contrary, without His word we have no ground to presume that He will be gracious to us, or to hope, based merely on our own imagination, for what He has not promised.

Moreover, the truth of the promise is made even more indisputable when God declares that He had made a covenant with His servant David, ratified by His own solemn oath. As it was customary in ancient times to engrave leagues and covenants on tablets of brass, a metaphor borrowed from this practice is used here.

God gives David two titles of distinction, calling him both His chosen and His servant. Those who would refer the former title to Abraham do not pay sufficient attention to the style of the Book of Psalms, in which it is quite common for one thing to be repeated twice.

David is called the chosen of God, because God, of His own good pleasure, and from no other cause, preferred him not only to the posterity of Saul and many distinguished individuals, but even to his own brothers. If, therefore, the cause or origin of this covenant is sought, we must necessarily return to the Divine election.

The title servant, which follows immediately after, is not to be understood as implying that David by his services merited anything from God. He is called God’s servant regarding the royal dignity, into which he had not rashly thrust himself, having been invested with the government by God, and having undertaken it in obedience to His lawful call.

When, however, we consider what the covenant essentially contains, we conclude that the prophet has not incorrectly applied it to his own use, and to the use of the whole people; for God did not enter into it with David individually, but had in view the whole body of the Church, which would exist from age to age.

The sentence, I will establish your throne forever, is partly to be understood concerning Solomon and the rest of David’s successors; but the prophet well knew that perpetuity, or everlasting duration, in the strict and proper sense, could be fulfilled only in Christ. In ordaining one man to be king, God certainly did not have regard for one house alone, while He forgot and neglected the people with whom He had previously made His covenant in the person of Abraham; but He conferred sovereign power upon David and his children, so that they might rule for the common good of all the rest, until the throne would be truly established by the advent of Christ.