Sayyiduna Abu Umamah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) returned from Khaybar, and he had two slaves with him. Sayyiduna Ali (may Allah be pleased with him) said: O Messenger of Allah, give us a servant. The Prophet (peace and blessings be upon him) said: "Take whichever of the two you wish." He said: You choose one for me. The Prophet (peace and blessings be upon him) said: "Take this one, and do not beat him, for I saw him praying on our return from Khaybar, and I have been forbidden to beat those who pray." Then the Prophet (peace and blessings be upon him) gave a slave to Sayyiduna Abu Dharr al-Ghifari (may Allah be pleased with him) and said: "Accept the instruction to treat him well." So Sayyiduna Abu Dharr al-Ghifari (may Allah be pleased with him) set him free. The Prophet (peace and blessings be upon him) asked him: "What has become of the slave?" He said: O Messenger of Allah, you commanded me to accept the instruction to treat him well, so I set him free.
Ahmad and al-Tabarani recorded it.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب العتق / 7221
Hadith Gradingمحدثین:قال الشيخ الألباني: وهذا إسناد حسن [سلسله احاديث صحيحه/الحدود والمعاملات والاحكام/حدیث: 1324]
Hadith Takhrij«اخرجه احمد فى المسند (258/5) ، أخرجه مسند أحمد برقم: 21650، وأخرجه المعجم الكبير للطبراني برقم: 8100»