John Calvin Commentary Exodus 32:13

"Remember Abraham, Isaac, and Israel, thy servants, to whom thou swarest by thine own self, and saidst unto them, I will multiply your seed as the stars of heaven, and all this land that I have spoken of will I give unto your seed, and they shall inherit it for ever." — Exodus 32:13 (ASV)

Remember Abraham, Isaac, and Israel, your servants; He does not bring them forward as patrons, by the assistance of whose voice he might obtain what he seeks; but because the promise was lodged with them, which they transmitted as an inheritance to their descendants. We must observe, then, the quality or character with which God had invested the Patriarchs. For this reason it is said in Psalm 132:1, Lord, remember David, and all his afflictions. And from this the ignorance and folly of the Papists are easily refuted, who imagine from these testimonies that the dead are ordained to be intercessors.

He also purposely refers to God’s oath, by which He had more solemnly bound Himself, so that His promise might be more sure and authoritative. The Apostle, in the Epistle to the Hebrews 6:13, tells us why God swears by Himself; namely, because he could swear by no greater; though sometimes to the same effect He swears by His throne in heaven, or His sanctuary.

Finally, it is uncertain whether there is a ὕστερον πρότερον or not in this prayer, for we will see as we proceed that when Moses returned a second time, he prayed for the preservation of the people, and was heard. Nor was this done in a moment; but he again occupied forty days in reconciling the people with God.

It seems probable to me that Moses, amazed at the horrible denunciation, immediately offered his prayer; and without receiving a reply promising pardon, came down in suspense to apply a remedy to the evil. For it was by no means likely that, after having heard so severe and weighty a threat, he would have interposed no supplications, when he was so deeply anxious for the safety of the people.