Augustine of Hippo

Secondly, he turns himself to those very persons to whom he has given so great hope, and to them while here living he speaks and exhorts: "Sing ye to God, psalm ye to His name" [Psalm 68:4]. Already on this subject in the exposition of the Title we have before spoken that which seemed meet. He sings to God, that lives to God: He psalms to His name, that works unto His Glory. …

Exposition on Psalm 68 ↗

Jerome

Sing to God, sing a psalm to his name. "Sing" — in Scripture this always signifies contemplation (theoria): that is, consider the mysteries and the meaning of divine Scripture. But "to make melody" (psallere) Scripture signifies as a good work: for example, that the hearing should furnish its own work, and likewise the mouth, and the eyes, and the hands, and all the members should as it were agree, and thus strike the psaltery in the virtues. Make a way for him who ascends above the sunset: the Lord is his name. …

Homily 7, on Psalm 67 ↗

Gregory the Dialogist

Thus the Psalmist says to them: Make a way for him who ascends over the setting. For the Lord ascended over the setting because from that by which he fell in his passion, from that same thing he manifested his greater glory by rising again. He ascended over the setting, namely, because he trampled down by rising again the death which he had endured. …

Forty Gospel Homilies, Homily 17 ↗