I know it’s originally a Psalm/prayer for King Solomon, so it was probably written by King David his father; but what is the relevance in CCC that the service conductor has to recite it? Is this a prayer for the king or queen of the country whereever we Celestians worship?
That Psalm is a Messianic Psalm. Solomon doesn’t have dominion from end to end and everlasting to everlasting so that Psalm doesn’t qualify him.
Verse 15 of that Psalm says daily shall he be praised. Why would you want to praise Solomon daily? And the Psalm also says his name shall endure as long as the sun and moon. Again, it says he shall redeem their soul from deceit and violence, and precious shall their blood be in his sight. This is clearly not in reference to Solomon, but rather, these are the things that are attributed to the Messiah (Christ).
The Psalm may have elements of Solomon in it, but ultimately, if it was a prayer for Solomon it didn’t come to pass because he had a divided kingdom. The only one who has a united Kingdom is Christ.
We read Psalm 72 in our Sunday service because we remind ourselves of the dominion of Christ. We invoke the dominion of Christ in our service.
He is The Lord over all things, the God of justice, and the God of mercy. So whenever we are in His presence, we use that as a reminder that He’s the only one who has dominion over all things.