Augustine of Hippo

"The lines have fallen to me in glorious places" (ver. 6). The boundaries of my possession have fallen in Thy glory as it were by lot, like as God is the possession of the Priests and Levites. "For Mine inheritance is glorious to Me." "For Mine inheritance is glorious," not to all, but to them that see; in whom because I am, "it is to Me."

Exposition on Psalm 16 ↗

Jerome

The cords have fallen to me in excellent places: for indeed my inheritance is excellent to me. In place of that one people, I have possessed the whole world as my inheritance; and from the world, not just anyone, but the strong. For this is what "in excellent places" means, which in Greek is said "among the strong": according to that, "The Lord is my strength and my refuge and my deliverer," and in another place, "The Lord is my strength and my praise." If, then, anyone is excellent and strong, he is of the Lord's inheritance. …

Homily 61, on Psalm 15 ↗

Thomas Aquinas

"Lines have been stretched out for me in splendid places." The rich measure land with a line. Deut. 32: "Jacob is the line of his inheritance." And therefore "portion" is called, as it were, "the line of a cord," that is, my portion falls to me in the best things, because nothing is better than God himself. Jer. …

Exposition on the Psalms of David ↗