It is narrated from Sayyiduna Ali (may Allah be pleased with him): The Messenger of Allah (peace and blessings be upon him) ordered me to sell two brothers from among the war captives, so I sold them. Then I came to the Messenger of Allah (peace and blessings be upon him) and informed him that they had been sold. He (peace and blessings be upon him) asked: "Did you separate them from each other?" I said: Yes. He (peace and blessings be upon him) said: "Take them back, and then sell them both together; do not separate them." This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it, and it has another chain which is also sahih on the condition of the two Shaykhs.