Sunan Abi Dawud, Hadith 4745

‘Ubaidah (al-salman) said : ‘Ali mentioned about the people of al Nahrawan, saying: Among them there will be a man with a defective hand or with a small hand. if you were not to overjoy. I would inform you of what Allah has promised (the reward for) those who will kill them at the tongue of Muhammad (May peace be upon him). I asked : Have you heard this from him? He replied : Yes, by the lord of the Ka’bah.

حَدَّثَنَا مُحَمَّدُ بْنُ عُبَيْدٍ، وَمُحَمَّدُ بْنُ عِيسَى، - الْمَعْنَى - قَالاَ حَدَّثَنَا حَمَّادٌ، عَنْ أَيُّوبَ، عَنْ مُحَمَّدٍ، عَنْ عَبِيدَةَ، ‏:‏ أَنَّ عَلِيًّا، ذَكَرَ أَهْلَ النَّهْرَوَانِ فَقَالَ ‏:‏ فِيهِمْ رَجُلٌ مُودَنُ الْيَدِ أَوْ مُخْدَجُ الْيَدِ، أَوْ مَثْدُونُ الْيَدِ لَوْلاَ أَنْ تَبْطَرُوا لَنَبَّأْتُكُمْ مَا وَعَدَ اللَّهُ الَّذِينَ يَقْتُلُونَهُمْ عَلَى لِسَانِ مُحَمَّدٍ صلى الله عليه وسلم ‏.‏ قَالَ قُلْتُ ‏:‏ أَنْتَ سَمِعْتَ هَذَا مِنْهُ قَالَ ‏:‏ إِي وَرَبِّ الْكَعْبَةِ ‏.‏

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also referenced under: Hadith 4763 (DarusSalam)