Thomas Aquinas, on Ps 24:18

“See my abjection and my labour; and forgive me all my sins.”

“The punishment assumed interiorly, however, is the humility of spirit before God; hence he says, "See," that is, consider, "my humility": Lk. 1: "He has regarded the humility of his handmaid." Likewise, there is also humility manifest exteriorly, which is a certain labor; hence he says, "and my toil": Ps. 72: "They are not in the labor of men," etc. Of good men it is said, Wis. 3: "Glorious is the fruit of good labors." Concerning guilt he says, "Forgive all my sins." Sir. 28: "Sins will be loosed for the one who prays." And note that through three things one obtains the forgiveness of sins: namely through tribulations, which work the forgiveness of sins if they are patiently borne: Tob. 3: "In the time of tribulation you forgive sins, and after the storm you make calm, and after weeping and tears you pour in rejoicing." Likewise through humility: 1 Kgs. 21: "Because Ahab humbled himself before me, I will not bring evil in his days": Ps. 50: "A contrite and humbled heart," etc. Likewise through labor: Deut. 26: "He looked upon our humility and our labor and distresses, and brought us out of Egypt with a mighty hand." And therefore he says, "Forgive all my sins."”

Imported from an open dataset — not yet checked against the printed edition.