Sahih Bukhari
Sahih Bukhari Volume 003, Book 046, Hadith Number 709.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 46. Manumission Of Slaves
Narated By Qais : When Abu Huraira accompanied by his slave came intending to embrace Islam, they lost each other on the way. (When the slave showed up) Abu Huraira said (to the Prophet), "I make you witness that the slave is free for Allah's Cause."