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كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(52)
Chapter: Leading somebody else's animal during the battle
(52)
باب مَنْ قَادَ دَابَّةَ غَيْرِهِ فِي الْحَرْبِ
Sahih al-Bukhari 2864

Narrated Abu 'Is-haq:

Somebody asked Al-Bar-a bin `Azib, "Did you flee deserting Allah's Messenger (ﷺ) during the battle of Hunain?" Al-Bara replied, "But Allah's Messenger (ﷺ) did not flee. The people of the Tribe of Hawazin were good archers. When we met them, we attacked them, and they fled. When the Muslims started collecting the war booty, the pagans faced us with arrows, but Allah's Messenger (ﷺ) did not flee. No doubt, I saw him on his white mule and Abu Sufyan was holding its reins and the Prophet (ﷺ) was saying, 'I am the Prophet (ﷺ) in truth: I am the son of `Abdul Muttalib.' "

حَدَّثَنَا قُتَيْبَةُ، حَدَّثَنَا سَهْلُ بْنُ يُوسُفَ، عَنْ شُعْبَةَ، عَنْ أَبِي إِسْحَاقَ،‏.‏ قَالَ رَجُلٌ لِلْبَرَاءِ بْنِ عَازِبٍ ـ رضى الله عنهما ـ أَفَرَرْتُمْ عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم يَوْمَ حُنَيْنٍ قَالَ لَكِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم لَمْ يَفِرَّ، إِنَّ هَوَازِنَ كَانُوا قَوْمًا رُمَاةً، وَإِنَّا لَمَّا لَقِينَاهُمْ حَمَلْنَا عَلَيْهِمْ فَانْهَزَمُوا، فَأَقْبَلَ الْمُسْلِمُونَ عَلَى الْغَنَائِمِ وَاسْتَقْبَلُونَا بِالسِّهَامِ، فَأَمَّا رَسُولُ اللَّهِ صلى الله عليه وسلم فَلَمْ يَفِرَّ، فَلَقَدْ رَأَيْتُهُ وَإِنَّهُ لَعَلَى بَغْلَتِهِ الْبَيْضَاءِ وَإِنَّ أَبَا سُفْيَانَ آخِذٌ بِلِجَامِهَا، وَالنَّبِيُّ صلى الله عليه وسلم يَقُولُ ‏ "‏ أَنَا النَّبِيُّ لاَ كَذِبْ أَنَا ابْنُ عَبْدِ الْمُطَّلِبْ ‏"‏‏.‏
Reference : Sahih al-Bukhari 2864
In-book reference : Book 56, Hadith 80
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 116
  (deprecated numbering scheme)