حَدَّثَنَا مُوسَی بْنُ إِسْمَعِيلَ حَدَّثَنَا حَمَّادٌ أَخْبَرَنَا عَطَائُ بْنُ السَّائِبِ عَنْ زَاذَانَ عَنْ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ أَنَّ رَسُولَ اللَّهِ صَلَّی اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ مَنْ تَرَکَ مَوْضِعَ شَعْرَةٍ مِنْ جَنَابَةٍ لَمْ يَغْسِلْهَا فُعِلَ بِهَا کَذَا وَکَذَا مِنْ النَّارِ قَالَ عَلِيٌّ فَمِنْ ثَمَّ عَادَيْتُ رَأْسِي ثَلَاثًا وَکَانَ يَجُزُّ شَعْرَهُ
سنن ابودوٗد · Hadith 249
Narrated Ali ibn Abu Talib: The Messenger of Allah ﷺ said: If anyone who is sexual defiled leaves a spot equal to the breadth of a hair without washing, such and such an amount of Hell-fire will have to be suffered for it. Ali said: On that account I treated my head (hair) as an enemy, meaning I cut my hair. He used to cut the hair (of his head). May Allah be pleased with him.
Sanad
حَدَّثَنَا مُوسَی بْنُ إِسْمَعِيلَ حَدَّثَنَا حَمَّادٌ أَخْبَرَنَا عَطَائُ بْنُ السَّائِبِ عَنْ زَاذَانَ عَنْ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ