John Calvin Commentary Psalms 56:12

"Thy vows are upon me, O God: I will render thank-offerings unto thee." — Psalms 56:12 (ASV)

Your vows are upon me, O God! I hinted from the outset that it is probable this psalm was written by David after he had escaped the dangers he describes; and this may account for the thanksgiving appended to it. At the same time, we have evidence that he was always ready to engage in this exercise, even while currently suffering under his afflictions.

He declares that the vows of God were upon him; by which he means that he was bound to pay them, just as among the Romans, a person who had obtained what he sought under engagement of a vow was said to be voti damnatus — condemned of his vow. If we have promised thanks, and our prayers have been heard, an obligation is contracted.

He calls them the vows of God — your vows; for the money in my hand may be said to be my creditor's, since I am in his debt. He views his deliverance as having come from God; and, the condition having been performed, he acknowledges himself to be burdened with the vows he had contracted.

We learn from the second part of the verse the nature of the vows to which he refers; and by paying attention to this, we can avoid the mistake of imagining that he sanctions any vows like those practiced among Papists. He says that he would render praises, or sacrifices of praise; for the word is applied to sacrifices, which were the outward symbols of thanksgiving.

David knew well that God attached no value to sacrifices considered in themselves, or regardless of the intention and spirit of the person offering them; however, we may believe that he would not neglect the sacred ceremonies of the Law that was imposed upon the Church at that time, and that he speaks of some solemn expression of gratitude, such as was customary among the Jews upon receiving a significant divine favor.