Sunan Abi Dawud, Hadith 3930

The tradition mentioned above has also been transmitted by Ibn 'Umar to the same effect through a different chain of narrators. Nafi' sometimes said: He will be emancipated to the extent of the share which he emancipated, and sometimes he did not say these words.

حَدَّثَنَا مُؤَمَّلٌ، حَدَّثَنَا إِسْمَاعِيلُ، عَنْ أَيُّوبَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ صلى الله عليه وسلم بِمَعْنَاهُ قَالَ وَكَانَ نَافِعٌ رُبَّمَا قَالَ ‏ "‏ فَقَدْ عَتَقَ مِنْهُ مَا عَتَقَ ‏" ‏ ‏.‏ وَرُبَّمَا لَمْ يَقُلْهُ ‏.‏

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also referenced under: Hadith 3941 (DarusSalam)