Sahih Muslim Book 015, Hadith Number 4093.
Chapter : Feeding of slave with what the master cats himself and clothing him with what he wears himself and not to burden him beyond capacity.
This hadith has been narrated on the authority of A'mash but with a slight variation of words, e.g. in the hadith transmitted on the authority of Zuhair and Abu Mu'awiya after his words (these words of the Holy Prophet): " You are a person having the remnants of Ignorance in him." (these words also occur, that Abu Dharr) said: Even up to this time of my old age? He (the Holy Prophet) said: Yes. In the tradition transmitted on the authority of Abu Mu'awiya (the words are): "Yes, in this time of your old age." In the tradition transmitted on the authority of 'Isa (the words are): "If you burden him (with an unbearable burden), you should sell him (and get another slave who can easily undertake this burden)." In the hadith transmitted on the authority of Zuhair (the words are): "Help him in that (work)." In the hadith transmitted by Abu Mu'awiya (separately) there is no such word: Then sell him or help him." This hadith concludes with these words: "Do not burden him beyond his capacity."