Sunan an-Nasa'i, Book 49, Hadith 40 (In-Book)

It was narrated that Jabir bin 'Abdullah said: "A man among the Ansar stated that his salve was to be set free after he died; he was in need, and he owed a debt. The Messenger of Allah [SAW] sold him (the slave) for eight hundred Dirhams, and he gave (the money) to him and said: 'Pay off your debt and spend on your dependents.'"

أَخْبَرَنَا عَبْدُ الأَعْلَى بْنُ وَاصِلِ بْنِ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا مُحَاضِرُ بْنُ الْمُوَرِّعِ، قَالَ حَدَّثَنَا الأَعْمَشُ، عَنْ سَلَمَةَ بْنِ كُهَيْلٍ، عَنْ عَطَاءٍ، عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ، قَالَ أَعْتَقَ رَجُلٌ مِنَ الأَنْصَارِ غُلاَمًا لَهُ عَنْ دُبُرٍ وَكَانَ مُحْتَاجًا وَكَانَ عَلَيْهِ دَيْنٌ فَبَاعَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم بِثَمَانِمِائَةِ دِرْهَمٍ فَأَعْطَاهُ فَقَالَ ‏ "‏ اقْضِ دَيْنَكَ وَأَنْفِقْ عَلَى عِيَالِكَ ‏" ‏ ‏.‏

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