Comentario sobre Deuteronómio 21:10

כי תצא למלחמה WHEN THOU GOEST FORTH TO WAR — Scripture is speaking here of a war that is not obligatory upon the Israelites (Sifrei Devarim 211:1), for in regard to a war that was waged against the inhabitants of Erez Israel, Scripture could not possibly say, “and thou hast captured captives”, since it has already been stated regarding them, (Deuteronomy 20:16) “[But of the cities of those people ...] you shall not allow any soul to live”.

כי תצא למלחמה על איביך, When you go to war against your enemies, etc. Why did the Torah need to write this whole introduction when it would have sufficed to write: "when you see an attractive woman amongst the prisoners, etc." The whole of verse one seems extraneous to the subject matter under discussion! Furthermore, seeing the Torah did decide to write: "when you go out to war against your enemies, etc.," why did we need the words "against your enemies?" Against whom does one go to war if not against one's enemies? Perhaps the reason is to be found in halachic relaxations which apply to troops in wartime. A woman such as the attractive woman prisoner mentioned here would be totally out of bounds if not for the fact that she was captured in war; the same applies to other relaxations of the halachah such as the prohibition of eating the hind parts of a pig, etc, (compare Chulin 17). This gave rise to the Torah using a different style in this instance. Seeing that the Jewish soldier was aware of the halachic relaxations which are applicable even to Torah law under conditions of war, the Torah was concerned lest some of the soldiers would actually look forward to the battle in order to avail themselves of these relaxations of Torah law. The Torah was keenly aware of this and reminded the soldier that when he goes to war his only purpose should be to avenge himself on the enemies of the Jewish people, not in order to have an excuse to indulge in things which are normally forbidden. The words כי תצא, "when you go out," are a reminder that although you depart from the normal rules of halachic restrictions when your life is at stake, למלחמה, your mind must concentrate only on the war, on the battle, not on what you consider the fringe benefits. The reason the Torah adds the words על איביך, "against your enemies," is to remind you that your enemies are G'd's enemies as we have been told by David in Psalms 139,21: "O Lord, You know I hate those who hate You, and I loathe Your adversaries." Your entire reason for going to war must be for this sole purpose. If that will be the case, then the Torah's assurance: "and the Lord your G'd will deliver them into your hand" will be fulfilled. From our verse (verse 1) you may deduce therefore that unless your motivation is the one the Torah expects of you, your success will not be assured.

כי תצא, beyond the boundaries of your land.