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كتاب المغازى
64  
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
Sahih al-Bukhari 4065

Narrated `Aisha:

When it was the day of Uhud, the pagans were defeated. Then Satan, Allah's Curse be upon him, cried loudly, "O Allah's Worshippers, beware of what is behind!" On that, the front files of the (Muslim) forces turned their backs and started fighting with the back files. Hudhaifa looked, and on seeing his father Al-Yaman, he shouted, "O Allah's Worshippers, my father, my father!" But by Allah, they did not stop till they killed him. Hudhaifa said, "May Allah forgive you." (The sub-narrator, `Urwa, said, "By Allah, Hudhaifa continued asking Allah's Forgiveness for the killers of his father till he departed to Allah (i.e. died).")

حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ لَمَّا كَانَ يَوْمَ أُحُدٍ هُزِمَ الْمُشْرِكُونَ، فَصَرَخَ إِبْلِيسُ لَعْنَةُ اللَّهِ عَلَيْهِ أَىْ عِبَادَ اللَّهِ أُخْرَاكُمْ‏.‏ فَرَجَعَتْ أُولاَهُمْ فَاجْتَلَدَتْ هِيَ وَأُخْرَاهُمْ فَبَصُرَ حُذَيْفَةُ فَإِذَا هُوَ بِأَبِيهِ الْيَمَانِ فَقَالَ أَىْ عِبَادَ اللَّهِ أَبِي أَبِي‏.‏ قَالَ قَالَتْ فَوَاللَّهِ مَا احْتَجَزُوا حَتَّى قَتَلُوهُ فَقَالَ حُذَيْفَةُ يَغْفِرُ اللَّهُ لَكُمْ‏.‏ قَالَ عُرْوَةُ فَوَاللَّهِ مَا زَالَتْ فِي حُذَيْفَةَ بَقِيَّةُ خَيْرٍ حَتَّى لَحِقَ بِاللَّهِ‏.‏ بَصُرْتُ عَلِمْتُ، مِنَ الْبَصِيرَةِ فِي الأَمْرِ، وَأَبْصَرْتُ مِنْ بَصَرِ الْعَيْنِ وَيُقَالُ بَصُرْتُ وَأَبْصَرْتُ وَاحِدٌ‏.‏
Reference : Sahih al-Bukhari 4065
In-book reference : Book 64, Hadith 110
USC-MSA web (English) reference : Vol. 5, Book 59, Hadith 394
  (deprecated numbering scheme)