Thomas Aquinas, on Ps 39:1

“Unto the end, a psalm for David himself.”

“In the preceding Psalms, the Psalmist invoked divine help against the malice of the wicked and showed the purpose of his caution; here, however, he treats of confidence in divine help. And concerning this he does two things. First, he describes this confidence itself. Second, he treats of the mercy that is the cause of confidence, at Ps. 40: "Blessed is he who understands." Concerning the first he does two things. First, he commemorates the confidence he has in God, continuing from past events. Second, by seeking future things, at "But you, O Lord." Concerning the first he does two things. First, he commemorates the confidence he has in God by recounting past benefits. Second, he shows the mercy of God through which he bestows benefits, at "You have done many things." This Psalm mystically treats of the change from the old covenant to the new. The title: "Unto the end, a Psalm of David." In other Psalms, the "end" is taken as referring to Christ. Rom. 10: "Christ is the end of the law." Here the "end" is taken as the new covenant, which is the end of the old. 1 Tim. 1: "The end of the commandment is charity." Concerning the first part, he commemorates three things. First, the efficacy of confidence in general. Second, he touches upon it in particular, at "He set." Third, he shows this to be present in others, at "Many shall see." Concerning the first he does two things. First, he touches upon the confidence, showing it to be efficacious. Second, the sign of confidence. He says therefore, "Waiting, I waited." This text is understood as meaning that David, in his own person, many times waited for divine help. But because he speaks in the person of the Church, it is better that it be understood as referring to the human race awaiting the grace of the new covenant. And he says, "Waiting, I waited for the Lord," to show continuity: because although he delayed, yet he did not fail: Hab. 2: "If he delays, wait for him, for he will surely come." And thus every just person ought always to remain in confidence in God, because he does not fail those who hope in him. Or it refers to the various states of those who waited: because the patriarchs and prophets and all others waited, as is commonly held. To the outward waiting he adds intention, when he says, "And he attended to me": because although God hears all, yet he does not attend to all, because not all are ordered to the good; and therefore, "He attended to me," that is, for my benefit. The sign of confidence is supplication: because no one finally asks unless he hopes to be heard. And therefore he says, "And he heard my prayers": Ps. 142: "He regarded the prayer of the humble, and he brought me out of the pit of misery."”

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