John Calvin Commentary Deuteronomy 5:23

"And it came to pass, when ye heard the voice out of the midst of the darkness, while the mountain was burning with fire, that ye came near unto me, even all the heads of your tribes, and your elders;" — Deuteronomy 5:23 (ASV)

And it came to pass, when ye heard.

So that the Israelites would not undervalue his teaching—because he had been appointed by God as their minister to them—Moses addresses this potential objection by reminding them that it was done at their own petition and request.

We know how proudly they were accustomed to reject him, as if they saw in him nothing but what was earthly and human. It was necessary, then, for God Himself to speak to rescue His servant from the contempt of posterity.

For the people themselves, having been convicted of their foolish and preposterous request, could never afterwards have any pretext for rejecting Moses, as if he had not demonstrated the truth of his calling. And here their astonishing perverseness revealed itself, in that they were not ashamed to refuse to believe the holy Prophet, after he had been validated by so many miracles.

Certainly, if they had been just and honest judges, it would have been sufficiently well-known and certain to them that Moses did not speak of himself or of his own impulse, but that he was the instrument of the Spirit. Yet the doctrine of God was scorned by these proud, perverse, and fretful people because it was brought to them by the hands of a mortal man.

Therefore, by their insistent desires, they draw God down from heaven to speak Himself; but immediately terror seizes their minds, so that they flee from His voice. Thus, experience taught them that there was nothing better for them than to hear God speaking to them through Moses, and they were instructed by the just consequence of their rashness to choose and prefer that way of teaching which they had previously spurned.

For if, in the future, they refused to believe Moses—whom they themselves had chosen as their mediator with God—they would make themselves guilty of gross and wicked defiance; and this is what he now rebukes them for.

It would have been worse than improper for them, after God had yielded to their prayers, to reject the very blessing they had earnestly sought from Him.

For this reason, he reminds them that after they had been eyewitnesses of God’s terrifying power, they had voluntarily asked that He should not speak to them anymore. And, so that they could not object that this was done by only a few, or thoughtlessly, or in a disorderly manner, he expressly states that these requests were presented by the heads of their tribes and their elders.