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كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(85)
Chapter: The wearing of a helmet
(85)
باب لُبْسِ الْبَيْضَةِ
Sahih al-Bukhari 2911

Narrated Sahl:

That he was asked about the wound of the Prophet (ﷺ) on the day (of the battle) of Uhud. He said, "The face of the Prophet (ﷺ) as wounded and one of his front teeth as broken and the helmet over his head was smashed. Fatima washed of the blood while `Ali held water. When she saw that bleeding was increasing continuously, she burnt a mat (of date-palm leaves) till it turned into ashes which she put over the wound and thus the bleeding ceased."

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ أَبِي حَازِمٍ، عَنْ أَبِيهِ، عَنْ سَهْلٍ ـ رضى الله عنه ـ أَنَّهُ سُئِلَ عَنْ جُرْحِ النَّبِيِّ، صلى الله عليه وسلم يَوْمَ أُحُدٍ‏.‏ فَقَالَ جُرِحَ وَجْهُ النَّبِيِّ صلى الله عليه وسلم وَكُسِرَتْ رَبَاعِيَتُهُ وَهُشِمَتِ الْبَيْضَةُ عَلَى رَأْسِهِ، فَكَانَتْ فَاطِمَةُ ـ عَلَيْهَا السَّلاَمُ ـ تَغْسِلُ الدَّمَ وَعَلِيٌّ يُمْسِكُ، فَلَمَّا رَأَتْ أَنَّ الدَّمَ لاَ يَزِيدُ إِلاَّ كَثْرَةً أَخَذَتْ حَصِيرًا فَأَحْرَقَتْهُ حَتَّى صَارَ رَمَادًا ثُمَّ أَلْزَقَتْهُ، فَاسْتَمْسَكَ الدَّمُ‏.‏
Reference : Sahih al-Bukhari 2911
In-book reference : Book 56, Hadith 124
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 159
  (deprecated numbering scheme)