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كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(123)
Chapter: Providing oneself with food
(123)
باب حَمْلِ الزَّادِ فِي الْغَزْوِ
Sahih al-Bukhari 2982

Narrated Salama:

Once the journey-food of the people ran short and they were in great need. So, they came to the Prophet to take his permission for slaughtering their camels, and he permitted them. Then `Umar met them and they informed him about it. He said, "What will sustain you after your camels (are finished)?" Then `Umar went to the Prophet (ﷺ) and said, "O Allah's Messenger (ﷺ)! What will sustain them after their camels (are finished)?" Allah's Messenger (ﷺ) said, "Make an announcement amongst the people that they should bring all their remaining food (to me)." (They brought it and) the Prophet (ﷺ) invoked Allah and asked for His Blessings for it. Then he asked them to bring their food utensils and the people started filling their food utensils with their hands till they were satisfied. Allah's Messenger (ﷺ) then said, "I testify that None has the right to be worshipped but Allah, and I am His Apostle. "

حَدَّثَنَا بِشْرُ بْنُ مَرْحُومٍ، حَدَّثَنَا حَاتِمُ بْنُ إِسْمَاعِيلَ، عَنْ يَزِيدَ بْنِ أَبِي عُبَيْدٍ، عَنْ سَلَمَةَ ـ رضى الله عنه قَالَ خَفَّتْ أَزْوَادُ النَّاسِ وَأَمْلَقُوا، فَأَتَوُا النَّبِيَّ صلى الله عليه وسلم فِي نَحْرِ إِبِلِهِمْ، فَأَذِنَ لَهُمْ، فَلَقِيَهُمْ عُمَرُ فَأَخْبَرُوهُ فَقَالَ مَا بَقَاؤُكُمْ بَعْدَ إِبِلِكُمْ فَدَخَلَ عُمَرُ عَلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَ يَا رَسُولَ اللَّهِ مَا بَقَاؤُهُمْ بَعْدَ إِبِلِهِمْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ نَادِ فِي النَّاسِ يَأْتُونَ بِفَضْلِ أَزْوَادِهِمْ ‏"‏‏.‏ فَدَعَا وَبَرَّكَ عَلَيْهِ، ثُمَّ دَعَاهُمْ بِأَوْعِيَتِهِمْ، فَاحْتَثَى النَّاسُ حَتَّى فَرَغُوا، ثُمَّ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ أَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ، وَأَنِّي رَسُولُ اللَّهِ ‏"‏‏.‏
Reference : Sahih al-Bukhari 2982
In-book reference : Book 56, Hadith 191
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 225
  (deprecated numbering scheme)