Sahih Bukhari
Sahih Bukhari Volume 003, Book 046, Hadith Number 727.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 46. Manumission Of Slaves
Narated By Abu Musa : The Prophet said, "The Mamluk (slave) who worships his Lord in a perfect manner, and is dutiful, sincere and obedient to his Saiyid (master), will get a double reward."