Hadith: Abu Musa Radiyallahu 'anhu narrates that Rasulullah
Sallallahu 'alaihi wasallam said: There are three types of people, who
will have a double reward: A man from among the people of the Book (Jew
or Christian), who believed in his Prophet and (also) believed in
Muhammad Sallallahu 'alaihi wasallam; a slave when he fulfils the rights
(duties) of Allah as well as the rights of his master; and a man who
possessed a maid-servant and brought her up in an excellent manner and
educated her with the best of knowledge and then set her free and
married her, for him is a double reward. (Bukhari: 97)
✺ Note: The objective of this hadith is to explain that a double reward
will be recorded in respect of each and every of their deeds, compared
with those of others. For example, if anyone offers Salat, he will
receive a tenfold reward and when anyone of them from these three
persons does the same action, his reward will be twenty-fold. (Mazahir
Haque)