עקידת יצחק
Akeidat Yitzchak 97:1
Q — Why does the Torah permit the captive woman at all? Why open the parsha with a concession to desire in the heat of war? How does this fit beside the war-laws that closed the prior parsha?
A — The Torah permitted the yefas to'ar as a concession to the yetzer — better to channel the drive within a bounded heter than to have a person fall into outright issur. Recognizing the force of desire at war, the Torah does not pretend it away but disciplines it: the prescribed waiting, the mourning, the deliberate process are designed to cool the impulse and often to dissolve it. The principle is realistic mastery of the yetzer — regulating what cannot simply be forbidden, so that permission itself becomes the instrument of restraint.
יבאר שהמלחמות המפורסמות הם למוד אל המלחמות הנסתרות כי הם היותר מסוכנות. וראית סוס ורכב וגו' כי תקרב אל עיר וגו':