Thomas Aquinas, on Ps 16:7

“Shew forth thy wonderful mercies; thou who savest them that trust in thee.”

“"Make wonderful." Here the petition is set forth, and it is twofold. The first concerns his own deliverance. The second concerns the overthrow of enemies: "Arise, O Lord, forestall him." Concerning the first, he does two things. First, he asks for deliverance. Second, he adds the necessity for deliverance, at "My enemies." Concerning the first, he does three things. First, he asks for mercy. Second, for salvation, at "You who save." Third, the manner of deliverance, at "Guard me as the pupil of the eye." He says, therefore, "Make wonderful." That someone should be delivered from a small enemy is not marvelous; but when someone is delivered from the greatest evil or enemy, this is marvelous; and this is what he asks: "Make wonderful," that is, deliver me wondrously. And this not according to human judgment, but according to your mercy. Sir. 36: "Renew signs and work new wonders; glorify your hand and your right arm; stir up fury and pour out wrath; lift up the adversary and afflict the enemy." And the reason for this is that it is yours and proper to you: "You who save those who hope in you." Sir. 2: "No one has hoped in the Lord and been confounded." "And you save from those who resist your right hand." The right hand of God, or his power, operates spiritually in good things: Prov. 3: "Length of days is in her right hand, and in her left hand riches and glory." The demons or sinners are said to resist the right hand of God, because they impede spiritual goods. Or the right hand of God is said to be Christ: Ps. 117: "The right hand of God has wrought power." The Jews resist this by contradicting his teaching: Jn. 7: "How does this man know letters, having never learned?" And by disparaging his works: Jn. 9: "This man is not from God, who does not keep the Sabbath." Lk. 11: "By Beelzebub, the prince of demons, he casts out demons." But there is a question against the Psalm (Ps. 75): "You are terrible, and who will resist you?" No one, therefore, can contradict his will: Job 9: "God, whose anger no one can resist." And it must be said that no one can effectively resist him, but one can have the will or purpose of resisting.”

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