Exodus 32:21

And Moses said unto Aaron,.... Having destroyed the calf, and thereby expressed his abhorrence of their idolatry, he examines the principal persons concerned, and inquires into the cause and reason of it, how it came about; and begins with Aaron, though his own brother, with whom along with Hur he had committed the government of the people during his absence; and therefore was justly accountable for such a transaction, which could not have been without his knowledge and consent: no mention is made of Hur, whether he was dead or no is not certain; the Jewish writers say he was, and that he was killed for reproving the Israelites for their wickedness; and it looks as if he was dead, since he was not in the examination, and we hear of him no more afterwards:

what did this people unto thee, that thou hast brought so great a sin upon them? as idolatry is, than which no sin can be greater, it being not only a breach of the first table of the law, but directly against God, against the very being of God, and his honour and glory; it is a denial of him, and setting up an idol in his room, and giving to that the glory that is only due to his name; and Aaron being the chief magistrate, whose business it was to see that the laws of God were observed, and to restrain the people from sin, and to have been a terror to evil doers; yet falling in with them, and conniving at them, he is charged with bringing sin upon them, or them into that; and is asked what the people had done to him, that he should do this to them, what offence they had given him, what injury they had done him, that he bore them a grudge for it, and took this method to be revenged? for it is suggested, had they used him ever so ill, he could not have requited it in a stronger manner than by leading them into such a sin, the consequence of which must be ruin and destruction, see Genesis 20:9 or else Moses inquires of Aaron what methods the people had made use of to prevail upon him to suffer them to do such a piece of wickedness; whether it was by persuasion and artful insinuations, or by threatening to take away his life if he did not comply, or in what manner they had wrought upon his weak side, to induce him to take such a step.