Abu Burdah ibn Abu Musa reported on his father’s authority that Allahs Messenger (SAW) said, “Three people will be given their reward twice. A slave who gives the right of Allah and the right of his master - so, he will be given his reward two times. And a man who has a female slave (who is) beautiful and he teaches her manners after which he emancipates her and marries her seeking thereby Allah’s pleasure - so, he will get his reward twofold. And, a man who believed in an earlier Scripture (Torah, Zabur, Injeel) and then comes to him the other Book (the Qur’an), so he believes in it (too) - so, he is given his reward two times”.
[Ahmed 19732, Bukhari 97, Muslim 154, Nisai 3344, Ibn e Majah 1956]
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