Abayah bin Rifa'ah (may Allah have mercy on him) narrates: Rifa'ah (may Allah be pleased with him) died in the time of the Prophet (peace and blessings be upon him), leaving a slave who did cupping, a water-carrying camel and a piece of land. He (peace and blessings be upon him) said: "As for the cupper, do not eat from his earnings; rather feed those earnings to the water-carrying camel." They said: The slave girl also earns? He (peace and blessings be upon him) said: "Do not eat from the earnings of the slave girl, for I fear that she will earn by means of her private parts."
Hadith Referenceالمعجم الكبير للطبراني / باب الراء / 4391