Whether Psalm 110 was composed against the background of some particular event in the history of the Hebrew monarchy, such as Solomon’s installation as king, the New Testament uniformly interprets it as messianic and applies it to Jesus. When Jesus asked (in Mark 12:35ff.) how the scribes of His day could say that the Messiah was David’s son, whereas the opening words of Psalm 110 acclaimed Him as David’s Lord, the messianic interpretation of the psalm was evidently common ground to Him and them. Its general messianic interpretation forms the background to its use in the apostolic preaching: the words “Sit at My right hand,” which by common consent were addressed to the Messiah, must be regarded as addressed to Jesus, the apostles claimed, since His death and resurrection had shown that He was the Messiah. Indeed, Jesus Himself at His trial claimed to be the one addressed in these words when He told His judges that they would from then on see the Son of Man seated at the right hand of the Almighty (Mark 14:62). This claim, condemned as blasphemy by the Sanhedrin, was held by the apostles to have been vindicated by the subsequent act of God.
It remained for the writer of Hebrews, however, to bring out further implications of the ascription of this psalm to Jesus, by taking along with the divine utterance of verse 1 (“Sit at my right hand …”) the further divine utterance of verse 4 (“You are a priest forever after the order of Melchizedek”).
The opening words of Psalm 110 form one of the earliest Christian testimonia to the Messiahship of Jesus. But the author of Hebrews takes up verse 4 of that psalm and applies it to Jesus in a way which, so far as we can tell, was unprecedented in the early church. In some strands of Jewish expectation, a distinction was made between the lay Messiah (the “Messiah of Israel” or prince of the house of David) and the priestly Messiah (the “Messiah of Aaron”). It has indeed been argued that the people to whom the epistle to the Hebrews was addressed were related to those groups which held a twofold messianic hope of this kind. But in Hebrews 5:5–10, they are assured that Jesus, who was acclaimed by God as the Davidic Messiah in Psalm 2:7, was also acclaimed by God as high priest in Psalm 110:4. Christians acknowledge not two Messiahs, but one, and that one is both priest and king.
