Iyas bin Salamah bin al-Akwa' narrates from his father (Sayyiduna Salamah bin al-Akwa', may Allah be pleased with him) that he said: We set out with our commander Sayyiduna Abu Bakr (may Allah be pleased with him), whom the Messenger of Allah (peace and blessings be upon him) had appointed over us. We went on a campaign against Banu Fazarah. When we drew near their water, we camped for the night at the order of Sayyiduna Abu Bakr (may Allah be pleased with him). When we had prayed the morning prayer, Sayyiduna Abu Bakr (may Allah be pleased with him) ordered the attack, and we came down upon the water. Sayyiduna Salamah (may Allah be pleased with him) said: I saw a group of people on a high place, among them children and women. I feared that they would reach the mountain before me, so I went after them and shot an arrow between them and the mountain, and they stood still. I brought them to Sayyiduna Abu Bakr (may Allah be pleased with him). Among them was a woman of Banu Fazarah wearing a garment of leather, and with her was her daughter, one of the most beautiful of the Arabs. Sayyiduna Abu Bakr (may Allah be pleased with him) gave me her daughter as an extra share. I did not uncover her garment until I came to Madinah. The Messenger of Allah (peace and blessings be upon him) met me in the market and said: "O Salamah, give the woman to me." I said: O Messenger of Allah, she pleases me, and I have not even lifted her garment. The Messenger of Allah (peace and blessings be upon him) fell silent and left me. The next day the Messenger of Allah (peace and blessings be upon him) met me again in the market and said: "O Salamah, give the woman to me, 'lillahi darru abik' (how excellent your father is)!" I said: O Messenger of Allah, she pleases me, and by Allah, I have still not lifted her garment. O Messenger of Allah (peace and blessings be upon him), she is yours. The narrator said: The Prophet (peace and blessings be upon him) sent her to the people of Makkah and in exchange for her freed many Muslims who were in their hands.
Imam al-Shafi'i (may Allah have mercy on him) said: Do you not see that giving wealth to the people at war and feeding them food is, in many situations, of greater strength to them than selling them one or two slaves?
The Messenger of Allah (peace and blessings be upon him) gave permission to Sayyidah Asma' bint Abi Bakr (may Allah be pleased with her) when she said: My mother has come to me, and she is a polytheist; shall I maintain ties with her? He (peace and blessings be upon him) said: "Yes."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18330