(18) Keep alive for yourselves.—The Israelites were allowed to make slaves of their captives. Shortly after the capture of these Midianitish women, and, it may be, as arising out of it, the law concerning marriage with captives was enacted. (See Deuteronomy 21:10-14.)

31:13-18 The sword of war should spare women and children; but the sword of justice should know no distinction, but that of guilty or not guilty. This war was the execution of a righteous sentence upon a guilty nation, in which the women were the worst criminals. The female children were spared, who, being brought up among the Israelites, would not tempt them to idolatry. The whole history shows the hatefulness of sin, and the guilt of tempting others; it teaches us to avoid all occasions of evil, and to give no quarter to inward lusts. The women and children were not kept for sinful purposes, but for slaves, a custom every where practised in former times, as to captives. In the course of providence, when famine and plagues visit a nation for sin, children suffer in the common calamity. In this case parents are punished in their children; and for children dying before actual sin, full provision is made as to their eternal happiness, by the mercy of God in Christ.Caused ... to commit trespass - More literally, "became to the children of Israel for a cause (or, incitement) of treachery to the Lord." 14-18. And Moses was wroth with the officers of the host—The displeasure of the great leader, though it appears the ebullition of a fierce and sanguinary temper, arose in reality from a pious and enlightened regard to the best interests of Israel. No order had been given for the slaughter of the women, and in ancient war they were commonly reserved for slaves. By their antecedent conduct, however, the Midianitish women had forfeited all claims to mild or merciful treatment; and the sacred character, the avowed object of the war (Nu 31:2, 3), made their slaughter necessary without any special order. But why "kill every male among the little ones"? It was designed to be a war of extermination, such as God Himself had ordered against the people of Canaan, whom the Midianites equalled in the enormity of their wickedness. Not known a man, to wit, carnally: See Poole "Ge 4:1 19:8 Leviticus 18:22.

Keep alive for yourselves; either to sell them as slaves to others, or to use them as servants to yourselves, or to marry them, when you have prepared and instructed them.

But all the women children,.... The females among the little ones:

that have not known a man by lying with him; which might be pretty clear, and easily concluded, from their age:

keep for yourselves; either to be handmaids to them, or to be married among them when grown up, and become proselytes, and initiated into their religion.

But all the women children, that have not known a man by lying with him, keep alive for yourselves.