John Calvin Commentary Exodus 3:13

"And Moses said unto God, Behold, when I come unto the children of Israel, and shall say unto them, The God of your fathers hath sent me unto you; and they shall say to me, What is his name? What shall I say unto them?" — Exodus 3:13 (ASV)

Behold, when I come to the children of Israel. If we believe that Moses expressed his own thoughts here, he would be saying that he could not be the messenger of an unknown God, which seems highly improbable. For who can think that the faith of the holy prophet was so erased that he had forgotten the true God, whom he had devoutly served? Indeed, in the name of his elder son, he had borne witness to his solemn remembrance of Him when he voluntarily declared himself a stranger in the land of Midian.

Nor does this seem any more fitting for the children of Israel, who constantly spoke of the covenant made with their fathers. However, it will not be far from the truth if we suppose that the faith of both Moses and the Israelites had grown somewhat faint and weak.

Moses himself, with his father-in-law, was entirely without the instruction that would keep him in that specific worship and knowledge he had absorbed in Egypt. The whole people, too, had strayed far from the ways of their fathers. For although the brightness of the true and ancient religion was not entirely gone, it still shone only in small sparks.

But while Moses tacitly confesses his ignorance, because he was not sufficiently familiar with the doctrine handed down from the holy patriarchs, yet because he was about to present himself to the people as a stranger, he infers that he will be rejected unless he brings with him some password that will be recognized.

“I will declare what You command,” (he seems to say), “that I am sent by the God of our fathers. But they will mock and despise my mission unless I present some more certain sign, from which they may learn that I have not falsely used Your name.” He therefore seeks a name that may be a distinguishing mark, since it is not a mere word or syllable in question here, but a testimony by which he may persuade the Israelites that they are heard because of the covenant with their fathers.