John Calvin Commentary Psalms 57:3

"He will send from heaven, and save me, [When] he that would swallow me up reproacheth; Selah God will send forth his lovingkindness and his truth." — Psalms 57:3 (ASV)

He shall send from heaven, and save me. David, as I have repeatedly had occasion to observe, interlaces his prayers with holy meditations for the comfort of his own soul, in which he contemplates his hopes as already realized in the event. In the words before us, he glories in the divine help with as much assurance as if he had already seen the hand of God interposed on his behalf.

When it is said, he shall send from heaven, some consider the expression as elliptical, meaning that he would send his angels; but it seems rather to be an indefinite form of speech, signifying that the deliverance David expected was not common, but a signal and miraculous one.

The expression denotes the greatness of the interposition he looked for, and heaven is opposed to earthly or natural means of deliverance.

What follows can be rendered in two different ways. We may supply the Hebrew preposition מ, mem, and read, He shall save me from the reproach; or it might be better to understand the words appositively: He shall save me, to the reproach of him who swallows me up. The latter expression might be rendered, from him who waits for me. His enemies gaped at him in their eagerness to accomplish his destruction and insidiously watched their opportunity; but God would deliver him, to their disgrace.

God is said to strike His enemies with shame and reproach when He disappoints their expectations. The deliverance David anticipated was signal and miraculous; and he adds that he looked for it entirely from the mercy and truth of God, which he here represents as the hands, so to speak, by which God extends His assistance to His people.