Narrated Abu Qatada:

When it was the day of (the battle of) Hunain, I saw a Muslim man fighting with one of the pagans and another pagan was hiding himself behind the Muslim in order to kill him. So I hurried towards the pagan who was hiding behind the Muslim to kill him, and he raised his hand to hit me but I hit his hand and cut it off. That man got hold of me and pressed me so hard that I was afraid (that I would die), then he knelt down and his grip became loose and I pushed him and killed him. The Muslims (excepting the Prophet (ﷺ) and some of his companions) started fleeing and I too, fled with them. Suddenly I met `Umar bin Al-Khattab amongst the people and I asked him, "What is wrong with the people?" He said, "It is the order of Allah" Then the people returned to Allah's Messenger (ﷺ) (after defeating the enemy). Allah's Messenger (ﷺ) said, "Whoever produces a proof that he has killed an infidel, will have the spoils of the killed man." So I got up to look for an evidence to prove that I had killed an infidel, but I could not find anyone to bear witness for me, so I sat down. Then it came to my mind (that I should speak of it) and I mentioned the case to Allah's Messenger (ﷺ). A man from the persons who were sitting with him (i.e. the Prophet), said, "The arms of the deceased one whom he ( i.e. Abu Qatada) has mentioned, are with me, so please compensate him for it (i.e. the spoils)," Abu Bakr said, "No, Allah's Messenger (ﷺ) will not give it (i.e. the spoils) to a weak humble person from Quraish and leave one of Allah's Lions who fights on behalf of Allah and His Apostle." Allah's Messenger (ﷺ) then got up and gave that (spoils) to me, and I bought with it, a garden which was the first property I got after embracing Islam.

وَقَالَ اللَّيْثُ حَدَّثَنِي يَحْيَى بْنُ سَعِيدٍ، عَنْ عُمَرَ بْنِ كَثِيرِ بْنِ أَفْلَحَ، عَنْ أَبِي مُحَمَّدٍ، مَوْلَى أَبِي قَتَادَةَ أَنَّ أَبَا قَتَادَةَ، قَالَ لَمَّا كَانَ يَوْمُ حُنَيْنٍ نَظَرْتُ إِلَى رَجُلٍ مِنَ الْمُسْلِمِينَ يُقَاتِلُ رَجُلاً مِنَ الْمُشْرِكِينَ، وَآخَرُ مِنَ الْمُشْرِكِينَ يَخْتِلُهُ مِنْ وَرَائِهِ لِيَقْتُلَهُ، فَأَسْرَعْتُ إِلَى الَّذِي يَخْتِلُهُ فَرَفَعَ يَدَهُ لِيَضْرِبَنِي، وَأَضْرِبُ يَدَهُ، فَقَطَعْتُهَا، ثُمَّ أَخَذَنِي، فَضَمَّنِي ضَمًّا شَدِيدًا حَتَّى تَخَوَّفْتُ، ثُمَّ تَرَكَ فَتَحَلَّلَ، وَدَفَعْتُهُ ثُمَّ قَتَلْتُهُ، وَانْهَزَمَ الْمُسْلِمُونَ، وَانْهَزَمْتُ مَعَهُمْ، فَإِذَا بِعُمَرَ بْنِ الْخَطَّابِ فِي النَّاسِ، فَقُلْتُ لَهُ مَا شَأْنُ النَّاسِ قَالَ أَمْرُ اللَّهِ، ثُمَّ تَرَاجَعَ النَّاسُ إِلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ مَنْ أَقَامَ بَيِّنَةً عَلَى قَتِيلٍ قَتَلَهُ فَلَهُ سَلَبُهُ ‏"‏‏.‏ فَقُمْتُ لأَلْتَمِسَ بَيِّنَةً عَلَى قَتِيلِي، فَلَمْ أَرَ أَحَدًا يَشْهَدُ لِي فَجَلَسْتُ، ثُمَّ بَدَا لِي، فَذَكَرْتُ أَمْرَهُ لِرَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ رَجُلٌ مِنْ جُلَسَائِهِ سِلاَحُ هَذَا الْقَتِيلِ الَّذِي يَذْكُرُ عِنْدِي فَأَرْضِهِ مِنْهُ‏.‏ فَقَالَ أَبُو بَكْرٍ كَلاَّ لاَ يُعْطِهِ أُصَيْبِغَ مِنْ قُرَيْشٍ، وَيَدَعَ أَسَدًا مِنْ أُسْدِ اللَّهِ يُقَاتِلُ عَنِ اللَّهِ وَرَسُولِهِ صلى الله عليه وسلم قَالَ فَقَامَ رَسُولُ اللَّهِ صلى الله عليه وسلم فَأَدَّاهُ إِلَىَّ، فَاشْتَرَيْتُ مِنْهُ خِرَافًا فَكَانَ أَوَّلَ مَالٍ تَأَثَّلْتُهُ فِي الإِسْلاَمِ‏.‏
Reference : Sahih al-Bukhari 4322
In-book reference : Book 64, Hadith 352
USC-MSA web (English) reference : Vol. 5, Book 59, Hadith 611
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