The LORD has sworn and will not change his mind, “You are a priest forever after the order of Melchizedek.”
PSALM 110 In this psalm David sets forth the perpetuity of Christ’s reign, and the eternity of his priesthood; and, in the first place, he affirms, That God conferred upon Christ supreme dominion, combined with invincible power, with which he either conquers all his enemies, or compels them to submit to him.
Commenting on Psalm 110:1-7
We have now reached the heart of the psalm, which is also the very centre and soul of our faith. Our Lord Jesus is a Priest King by the ancient oath of Jehovah: "he glorified not himself to be made an high priest, "but was ordained there unto from of old, and was called of God an high priest after the order of Melchizedek.
Some have called this psalm David's creed, almost all the articles of the Christian faith being found in it; the title calls it David's psalm, for in the believing foresight of the Messiah he both praised God and solaced himself, much more may we, in singing it, to whom that is fulfilled, and therefore more clearly revealed, which is here foretold.
Commenting on Psalm 110:1-4