Ps 89:12

“"So make your right hand known that fettered we may gain wisdom of heart." Some codices say "trained"; others "fettered." "Trained" implies one thing; "fettered," another. What, then, is the meaning of "make your right hand known"? Why have you restrained your right hand so long, God? "Why draw back your hand and keep it idle beneath your garment?" says another psalm. Here is its meaning: we are lying prostrate in sickness; we are powerless in our sins; send forth your right hand and raise us up. Why do you keep your right hand so long idle beneath your cloak? Your heart overflows with a goodly theme;37 send forth your right hand and set us free. Make known to us the mystery that has been hidden from generation to generation. "Make your right hand known." What are you pilfering, Arius? The psalmist did not say, "Make your right hand," for God was never without his right hand. But what did he say? Your right hand, that you have always had and that has been in your bosom, make it known to us. Because we are not able to know him abiding in his Godhead, he assumes our humanity, and in that way we know him.”

“"Make Your right hand so well known" [Psalm 90:12]. This is the reading of most of the Greek copies: not of some in Latin, which is thus, "Make Your right hand well known to me." What is, "Your right hand," but Your Christ, of whom it is said, And to whom is the Arm of the Lord revealed? [Isaiah 53:1] Make Him so well known, that Your faithful may learn in Him to ask and to hope for those things rather of You as rewards of their faith, which do not appear in the Old Testament, but are revealed in the New: that they may not imagine that the happiness derived from earthly and temporal blessings is to be highly esteemed, desired, or loved, and thus their feet slip, when they see it in men who honour You not: that their steps may not give way, while they know not how to number Your anger. Finally, in accordance with this prayer of the Man that is His, He has made His Christ so well known as to show by His sufferings that not these rewards which seem so highly prized in the Old Testament, where they are shadows of things to come, but things eternal, are to be desired. The right hand of God may also be understood in this sense, as that by which He will separate His saints from the wicked: because that hand becomes well known, when it scourges every son whom He receives, and suffers him not, in greater anger, to prosper in his sins, but in His mercy scourges him with the left, that He may place him purified on His right hand. [Matthew 25:33] The reading of most copies, "make Your right hand well known to me," may be referred either to Christ, or to eternal happiness: for God has not a right hand in bodily shape, as He has not that anger which is aroused into violent passion.”

“So teach the number of our days And just as in the beginning, make known in the world the number of our long days, and since we enjoy longevity, we will be able to acquire intelligence, and we will acquire in them a heart of wisdom. The word נביא is an expression of bringing [rather than of a prophet. Cf. B.B. 12a, Targum ad. loc, Redak below]. (Some say: According to the number of our days כן, according to the numerical value of כן, seventy years. He says: According to the number of our years, which are few, so shall You chastise us, as [Jud. 8:16]: “and with them he chastised (ויודע) the men of Succoth.” This does not appear in all editions.)”

“Thy right hand. Your Messias, to liberate and instruct us. (St. Augustine) — “Make us know how to number our days thus, and we shall come to thee with a wise heart.” (St. Jerome) (Ecclesiasticus vii. 40.) (Haydock) — Septuagint have read iminoc for yamenu, “our days.” (Amama) — Make us truly wise, (Sa) or acquainted with teachers of truth. (Bellarmine) (Menochius)”