Thomas Aquinas, on Ps 24:6

“Remember, O Lord, thy bowels of compassion; and thy mercies that are from the beginning of the world.”

“"Remember." Here he asks for the forgiveness of sins, etc. Here he does two things. First, he presents the petition in general. Second, he explains it in detail, at "The sins." In general, however, he asks for mercy. This properly regards misery. The greatest misery is guilt. Now misery is opposed to happiness, which consists principally in the act of perfect virtue. Secondly, in external goods. Therefore misery consists principally in the act of sin. Secondly, in losses and external things: Prov. 14: "Sin makes peoples miserable." And therefore he asks for mercy against sins. In this mercy, therefore, there are two things: namely the use or effect of mercy, which is called commiseration. The second is mercy itself, which is called mercy insofar as it is a virtue. When therefore God has mercy in act, then he is called merciful; but he seems to forget when he does not have mercy in act; hence he says, "Remember your compassions": Ps. 76: "Will God forget to have mercy?" Yet the very fact that he delays having mercy, he does for our good, although in the opinion of men he seems to have forgotten when he does not have mercy in act; as if to say, remember, lest among the wicked you seem to have forgotten. "And your mercies." He says this on account of the many effects of divine mercy toward human nature: "which are from eternity," that is, from the beginning of creation: Lk. 1: "His mercy is from generation," etc.”

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