It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that if it were not for two things, I would have preferred to remain a slave in someone’s possession, because a slave cannot dispose of his wealth, and the reason for this is that I heard the Noble Prophet (peace and blessings be upon him) say: When a slave fulfills the rights of both Allah and his master, he receives double reward for every deed.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 9840