Augustine of Hippo

"The Lord from Heaven has looked forth upon the sons of men, that He might see if there is one understanding and seeking after God" [Psalm 53:3]. What is this? "Corrupted they are," all these that say, "There is no God"? And what? Did it escape God, that they had become such? Or indeed to us would their inward thought be opened, except by Him it were told? If then He understood, if then He knew, what is this which has been said, "that He might see"? For the words are of one inquiring, of one not knowing. …

Exposition on Psalm 53 ↗

Thomas Aquinas

"All have turned aside." And first he touches upon the departure from the root. Second he says what follows from this. And concerning this he explains. He says, therefore, he inquires here, but he finds that "all have turned aside, together they have become useless"; and again, "there is none who does good." From the understanding and seeking of God "all have departed." Is. 53: "Each one has turned aside to his own way." From this it follows that they are useless, both to themselves and to others. …

Exposition on the Psalms of David ↗