It is narrated from Abu Huraira (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "It is the right of the slave to have food and clothing in a good manner from his master, and he should only be assigned work according to his capacity."
Hadith Referenceمسند الإمام الشافعي / كتاب العتق والولاء والمدبر والمكاتب وحسن الملكة / 1100
Hadith Takhrijاخرجه مسلم الایمان، باب اطعام المملوك مما يأكل، والباسه مما يلبس، ولا يكلفه ما يغلبه (1662)۔