The Prophet ﷺ forbade the earnings of female slaves.
نهى النبي ﷺ عن كسب الإماء.
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Bukhari narrated it in the chapter on hiring (2283), from Muslim bin Ibrahim, who said, Shuba narrated to us, from Muhammad bin Jahada, from Abu Hazim, from Abu Hurairah, and he mentioned it.Ibn Hibban also narrated it in his Sahih (5159) from the hadith of Shuba with his chain of transmission, adding at the end, "for fear that she might commit fornication." If this addition is preserved, then what is meant here is fornication specifically, not work in the general sense.