Deuteronomy 21:13

Ver. 13. And she shall put the raiment of her captivity from off her— The French renders this more clearly: and she shall put off the raiment which she wore when she was taken captive; evidently to put on more vile apparel, and such as was better suited to the state and habit of mourning. In this dress she was to bewail her father and mother, either as slain in the war, or as likely to be seen no more by her; and this mourning was to continue a full month, the time usually allowed the Jews to bewail their deceased relations. The Talmudists add, that during this time she was to be instructed in the Jewish religion; for no indications of idolatry were to be tolerated among the Hebrews. Philo has justly observed, that the wisdom and humanity of Moses are very remarkable in this law; whereby the soldiers are forbidden to indulge a hasty and brutal passion, are kept a whole month in abstinence, and thereby have an opportunity given them of knowing the temper and disposition of the woman; for whose misfortune in captivity a compassionate provision is made, by allowing her so long a time of separation and mourning.