Sunan Abi Dawud, Hadith 4517

Qatadah transmitted the tradition mentioned above through a chain of narrators like that of Shu'bah. This version adds: Then al-Hasan forgot this tradition, and he used to say: A free man is not to be killed for a slave.

حَدَّثَنَا الْحَسَنُ بْنُ عَلِيٍّ، حَدَّثَنَا سَعِيدُ بْنُ عَامِرٍ، عَنِ ابْنِ أَبِي عَرُوبَةَ، عَنْ قَتَادَةَ، بِإِسْنَادِ شُعْبَةَ مِثْلَهُ زَادَ ثُمَّ إِنَّ الْحَسَنَ نَسِيَ هَذَا الْحَدِيثَ فَكَانَ يَقُولُ ‏ "‏ لاَ يُقْتَلُ حُرٌّ بِعَبْدٍ ‏" ‏ ‏.‏

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also referenced under: Hadith 4503 (Hasan)