Musnad Ahmad 937:226

Abdullah ibn al-Walid narrated to us, Sufyan narrated to us, from Mansur, from Mujahid, from Muwarriq al-Ijli, from Abu Dharr, from the Prophet, peace and blessings of Allah be upon him, who said: "Whoever among your servants is compatible with you, then feed them from what you eat, and clothe them from what you wear. And whoever among your servants is not compatible with you, then sell them, and do not torment the creation of Allah."