Numbers 31:14 - Coke's Commentary on the Holy Bible

And Moses was wroth with the officers— The Israelites obeyed the order in general; but, with a false pity, saved the lives of those Midianitish women whom they ought to have treated with the utmost rigour. They did not look upon them with that horror which they ought to have had for such seducers, but rather with a complacence, owing, perhaps, to a remembrance of their past criminal pleasures. This very justly provoked the spirit of Moses, by whose peremptory command sentence was immediately passed on all those women who had committed fornication with the Israelites, and all the male children which proceeded from that infamous commerce. The women children, Numbers 31:18 who were too young to be corrupted by unchastity or idolatry, were to be kept alive for themselves, either to be employed as servants, or, in case they turned proselytes, to marry with themselves, after the preparations required, Deuteronomy 21:11; Deuteronomy 21:23. Moses, I doubt not, followed some particular order which God had given him in this matter. But if this were not the case, the Israelites ought to have believed, that what was most odious in the sight of God in the whole country of Midian, was these impure and idolatrous women, who had seduced them to impurity and idolatry. They ought to have known, that the best use they could make of the sword which God had put into their hands, was to turn it against such notorious offenders. Thus the guilt of this people was so highly aggravated, that they were punished more severely than any other nations with whom they were at war, except those of Canaan; the like execution was, indeed, performed in after-times. See Judges 21:11. Saurin as above, and Virgil, AEn. ii. ver. 584, &c.