(7) They slew all the males.--The reference appears to be to those who were engaged in the war. The words do not refer to the whole of the male population, as appears from Numbers 31:17; and it is probable that many of the Midianites who were not engaged in the war withdrew from the scene of conflict. The reference in this verse, unless the words are inserted proleptically, seems to be to the whole of the adult males who fell into the hands of the Israelites during the war.

31:7-12 The Israelites slew the Kings of Midian. They slew Balaam. God's overruling providence brought him thither, and their just vengeance found him. Had he himself rightly believed what he had said of the happy state of Israel, he would not have thus herded with the enemies of Israel. The Midianites' wicked wiles were Balaam's projects: it was just that he should perish with them, Ho 4:5. They took the women and children captives. They burnt their cities and castles, and returned to the camp.And they warred against the Midianites, as the Lord commanded Moses,.... Whether the Midianites came out against them with an army, and there was a pitched battle between them, is not certain; however the Israelites committed acts of hostility upon them, by entering their cities, plundering their houses, and slaying the inhabitants of them; the Targum of Jonathan is,"they warred against Midian, and surrounded it in the three corners of it, as the Lord commanded Moses;''for, as Maimonides (b) observes from tradition,"when they besiege a city to take it, they do not surround it in the four corners of it, but in the three corners of it, and leave a place to flee out, that everyone that would might escape for his life, as it is said, "and they warred against Midian, as the Lord commanded Moses"; by report, or from tradition, it is learnt that so he commanded him;''that is, in such a manner to besiege a city; but for this there is only tradition, for it is not mentioned among the rules after directed to in such a case, Deuteronomy 20:10,

and they slew all the males; which fell into their hands; for, no doubt, there were multitudes that made their escape, since in later times we read of the Midianites, as a very powerful people, and very distressing to Israel, Judges 6:1 these, as Aben Ezra observes, they slew, were such as were grown up, for as for their little ones, them they spared and carried captive, Numbers 31:9.

(b) Hilchot Melacim, c. 6. sect. 7.