Saul attempts to kill David (the harpist of Israel) — Gustave Doré, Doré's English Bible (1866), public domain
Psalms — The canon's longest book — 150 Psalms edited into five doxology-bookended books, composed across a millennium, attributed to David, Asaph, Korah's sons, Moses, Solomon, Heman, Ethan, and anonymous voices. A ''Torah of David''; the Bible's longest continuous liturgical-devotional corpus.
Canon
Old Testament
Author
David principally (73 Psalms + 2 NT-cited); Asaph, Sons of Korah, Solomon, Moses, Heman, Ethan; ~50 anonymous.
Date
Composed c. 1400 BC (Mosaic Ps 90) through the post-exilic period (Ps 126 ''when the Lord turned again the captivity of Zion''). Roughly a millennium of composition; editorial compilation likely into the Persian period.
"Sound the trumpet at the beginning of the month, on the day of your notable solemnity." We must also consider that we are commanded through the instruments of the musical discipline both to play the lyre for the Lord and to observe the day of …
Cassiodorus· EXPOSITIONS OF THE PSALMS 80:4, 585patristic
Related commentary
“For it is a commandment for Israel, and a judgment of the God of Jacob. What is the commandment of God? To sing to God in victory: not to think it one's own, but the Lord's.
“Ver. 4. For this was a statute for Israel, and a law of the God of Jacob. It was a precept binding upon all the tribes that a sacred season should be set apart to commemorate the Lord's mercy; and truly it was but the Lord's due, he had a right and a claim to such special homage. When it can be proved that the observance of Christmas, Whitsuntide, and other Popish festivals was ever instituted by a divine statute, we also will attend to them, but not till then.
“Note, Praising God is not only a good thing, which we do well to do, but it is our indispensable duty, which we are obliged to do; it is at our peril if we neglect it; and in all religious exercises we must have an eye to the institution as our warrant and rule: "This I do because God has commanded me; and therefore I hope he will accept me;" then it is done in faith.
Matthew Henry· Commentary on the Whole Bible, 1710puritan