Abu Dawud Book 24, Hadith Number 3954.

Narated By AbuNajih as-Sulami : Along with the Apostle of Allah (PBUH) we besieged the palace of at-Ta’if. The narrator, Mutadh, said: I heard my father (sometimes) say: “Palace of at-Ta’if,” and (sometimes) “Fort of at-Ta’if,” which are the same.

I heard the Apostle of Allah (PBUH) say: he who causes an arrow to hit its mark in Allah’s cause will have it counted as a degree for him (in Paradise). He then transmitted the rest of the tradition.

I heard the Apostle of Allah (PBUH) say: If a Muslim man emancipates a Muslim man, Allah, the Exalted, will make every bone of his protection for every bone of his emancipator from Hell; and if a Muslim woman emancipates a Muslim woman, Allah will make every bone of hers protection for every bone of her emancipator from Hell on the Day of Resurrection.