Komentaryong Sumisipi para sa Deuteronomio 21:11

Therefore, the Torah also writes. “You take some of them captive. And you see among the captives a beautiful woman” [21:10–11]. This means, when you will see a beautiful woman in the war and will want to marry her. Here the Torah commanded that you should not hurry when you want to marry her. You should sleep with her once during the war, expecting you will quiet your evil inclination. However, you should not sleep with her again in the war. You have to bring her home first. The Torah knows well that someone is wanton during the war and will not be able to refrain from engaging in illicit sex. Therefore, it is better that the Torah allowed him one time, which is like not at all. When the evil inclination strengthens within him and he will want to sleep with her again, then he must first cut her hair and have her nails grow, and must remove her beautiful clothes, since when the nations go to war, they put on beautiful clothes, so that people should come to them to engage in illicit sex. Therefore, he has to wait thirty days, expecting that she will mourn her father and mother, after she heard that they had been killed. Another explanation for why he must wait thirty days. He should not sleep with her, expecting that in the meantime his inclination will subside and she will become disgusting to him, because she must mourn. She must cut her hair, let her nails grow and don despicable clothes and he will see her crying. Perhaps, he will send her away. Another explanation that he must wait thirty days, expecting that she will forget her father and mother who worshiped foreign gods and cleave to her husband who is a Jew. She will convert and she will be modest, and not like the nations who ware brazen, and run from one house to another house. Afterwards, the man says that she should cut her hair. Just like when a woman immerses herself, she must carefully examine her hair and comb it out. So too, the woman had to cut her hair, since she cannot be warned about properly cleaning her hair as it should be done. Afterwards, she cleans her nails, so that there should not be anything under them, so that her immersion should be properly done. She removes the clothes that she wore when she was menstruating.³Bahya, Deuteronomy, 21:11, 13.

"Be fruitful and multiply, etc." It is not far fetched to say that the reason the Torah exempted women from the mitzvah of Pru U'Rvu and obligated only men is because the laws of Hashem and His ways "... are pleasant and all of his paths peaceful" [Mishlei 3:17] and he did not amass on a Jewish person what the body can not tolerate. Everything that is prohibited by the Torah there is a permitted alternative as detailed in [Tractate Hullin 8th chapter] "Kal Habasar". Due to this principle there is only one day in the calendar th at we are [biblically] obligated to not eat [Yom Kippur] and the preceding day [the 9th] we are warned and obligated TO eat. Similarly the Torah does not prevent marital relations from any creature besides for Moshe Rabenu because there was no one else as exalted and required such carefulness with his body as Moshe. Similarly, the during wartime when the [Jewish] army is successful and the passions run high Hashem realized there is no way to stop the [soldiers wild] spirit as he desires the beautiful [captive] women [Deuteronomy 21:11] and the Torah allowed this women to the soldier [as outlined by Deuteronomy 21:11]. The Torah is only bending in response to evil inclinations and passions. This principle [of the Torahs ways are pleasant] became a corner stone of legal policy to our predecessors who established laws and exempted a Yibum who's children died after her husband died. Women endanger themselves in pregnancy and childbirth, that has been established as a legal principle that death is prevalent [see Tosfos Ketubot 83b]. As a result women are not commanded with the mitzvah of Pru U'Rvu. For the same reason a woman is allowed to drink a potion that makes her sterile [from having children] as Yehudit the wife of Rav Hiya [Yevamot 65b]. Women desire to have children is much stronger than men, as we see with Rachel who demanded from Jacob children "or its as if I'm dead". This explains what Rav Yosef said in Tractate Yevamot [65b] that women are exempt from Pru U'Rvu. The verse states "I am El-Shadai, Pre Urve" [singular form] and it doesn't use the plural form Pru U'Rvu. Adam and Even who were commanded together with Pru U'Rvu were commanded before the first sin and at that time there was no pain associated with childbirth. Therefore it was a mitzvah for both Adam and Eve to Pru U'Rvu. After the sin when there is pain in childbirth and frequently can be dangerous and life threatening [its not longer a mitzvah for women]. We see that women are known to swear never to become pregnant again while in labor. Noah [after he left the arc] was commanded with Pru U'Rru [in the plural form, and this was after the first sin], however the Torah in the verses preceding the command its written in the Torah that G-d blessed Noah and his sons, whereas their wives are not mentioned, since they are not obligated in the command of Pru U'Rvu. By Jacob its written "Pre Urve" [Genesis 25:1] [in the singular form] which is accurate [way the command should have been addressed]. The Maharsha in his commentary to Tractate Sanhedrin 55...