Traditionally ascribed to David (Matt. 22:43-45), this was most likely a coronation psalm for the Davidic kings. The two authoritative words, or oracles, from God (vv. 1, 4) maybe echoes of the covenant made with David concerning his dynasty (2 Sam. 7; Ps. 89: 1-37). The first of these oracles proclaims the sure triumph of the LORD's anointed (st. 1) and the refreshing dedication of the king's servants. The second oracle proclaims the king's enduring priesthood "in the order of Melchizedek" (st. 2; see Heb. 5:6,10; 7:15-22)–perhaps because the king in Jerusalem was responsible for building and maintaining the temple, for overseeing the work of the priests and Levites there, and for interceding for the nations. This blessed king would rule all the nations, judge them, and know unfailing vigor in his exalted eternal reign (st. 3). The New Testament uses Psalm 110 more than any other in reference to Jesus Christ as the anointed King filling this role. The versification (altered) is from the 1912 Psalter.
Psalter Hymnal Handbook
The confessions make it clear that the ascension of Christ opened the door to the rule of his kingdom. This fact is comforting to those who love him and is a fearful threat to those who despise him. The response therefore is praise and adoration from people of faith, and resistance from those who reject him.
Our World Belongs to God, paragraph 27 affirms “All authority, glory and sovereign power are given to him,” and reaffirms it in paragraph 43: “Jesus Christ rules over all.”
Consider the clear affirmation made in Heidelberg Catechism, Lord’s Day 19, Question and Answer 50: “Christ ascended to heaven to show there that he is the head of his church, the one through whom the Father rules all things.”
It is no wonder that those who despise him join together to conspire against him, for Christ’s aim as Lord is to “destroy the devil’s work…every force which revolts against you and every conspiracy against your holy word” (Heidelberg Catechism, Lord’s Day 48, Question and Answer 123).