John Calvin Commentary Numbers 25:6

"And, behold, one of the children of Israel came and brought unto his brethren a Midianitish woman in the sight of Moses, and in the sight of all the congregation of the children of Israel, while they were weeping at the door of the tent of meeting." — Numbers 25:6 (ASV)

And, behold, one of the children of Israel came. Moses here relates a case that was foul and detestable beyond others. There is no doubt that many, in the midst of such gross licentiousness that had now generally prevailed for some time, had filled the camp with various scandalous offenses; but there was something peculiarly enormous in the atrocity of this act, because this impious despiser of God wantonly insulted both God and men amid the tears and lamentations of all, as if he were triumphing over all shame and modesty.

The multitude were weeping before the tabernacle, that is to say, all the pious who trembled at the thought of approaching calamity, because they were fully persuaded that this licentiousness, accompanied by idolatry and sacrilege, would not go unpunished. Meanwhile, this abandoned man rushes forward and, in mockery of their tears, leads his harlot in procession, as it were.

No wonder, therefore, that God should have exercised such severity when things had come to this extremity. But it must be observed that the order of the history is inverted, because it is not credible that, after the Judges had begun to perform their office, such an iniquity would be committed. But this narrative is inserted in this way so that it may be more apparent how necessary it was to proceed speedily to severe chastisement, because otherwise it would have been impossible to apply a remedy in time to so desperate an evil.