John Calvin Commentary Exodus 3:16

"Go, and gather the elders of Israel together, and say unto them, Jehovah, the God of your fathers, the God of Abraham, of Isaac, and of Jacob, hath appeared unto me, saying, I have surely visited you, and [seen] that which is done to you in Egypt:" — Exodus 3:16 (ASV)

Go and gather. Because it was not easy either to gather all the people into one place, or for his commission to be heard by so great a multitude, Moses is commanded to begin with the elders, and to speak to them about their coming deliverance, so that by their authority they might thus arouse the body of the people to a good hope. For their dismissal must be sought from the king in the name of all, and all their minds prepared for departure, since, unless they had timely notice of it, there would have been no general consent to embrace the mercy of God.

It was then of great importance that Moses’s vocation should be well known, so that they might boldly follow him as the leader set over them by God.

He does not state without purpose that the God who had appeared to him was the God of Abraham, Isaac, and Jacob. This was because the vision, which the people would otherwise have hardly believed, depended on the ancient covenant entrusted to them.

Therefore, to gain belief for his words, Moses reminds them that the deliverance he was now about to address, and for which God appointed him as leader, was formerly promised in Abraham, Isaac, and Jacob. Lastly, because we usually struggle to accept what is new and strange, Moses therefore lays his foundation on the old revelations, which were beyond all doubt.

But he repeats what he had previously related was said to him, thus presenting to the others what he had privately heard, which confirmed his vocation.

We know that when God does not immediately help us in our adversities, our minds are worn down with grief and sink into despair, because we think that God does not care for us. Therefore, to prevent the Israelites from losing hope, Moses is commanded to tell them that it is God’s time to remember them. Although he might seem not to see them for a while, yet he would not forget his own people forever.

What follows, that the injuries done to them by the Egyptians had been taken into account, is added for confirmation. For, since he is judge of the world, he cannot help but rise as an avenger after long endurance of injustice and tyranny.

Let us also learn from this passage that when God seems to turn his face away from us by delaying his help, we should wait patiently until he looks upon us in due season, since his forgetfulness is only temporary when he gives us over to the will of our enemies.

I have shown elsewhere how these phrases are to be understood: namely, that according to the perception of our own senses, things are attributed to God that do not properly belong to him.