Deuteronomy 31:19 - Joseph Benson’s Commentary on the Old and New Testaments

Now, therefore, write this song Recorded in the next chapter, the contents of which were put into a song, that they might be better learned and more fixed in their minds and memories. For it has always been thought the most profitable way of instructing people, and communicating things to posterity, to put them into verse. For which reason Aristotle reports that people anciently sung their laws. And Tully tells us it was the custom of the ancient Romans to have the virtues and praises of their famous men sung at their feasts. Teach it the children of Israel Cause them to learn and understand it, and have it daily in their mouths. That this may be a witness for me Of my kindness in giving them so many blessings, of my patience in bearing so long with them, of my clemency in giving them such fair and plain warnings, and of my justice in punishing such an incorrigible people.