Imam Sadiq (peace be upon him): The letter of Imam Sadiq (peace be upon him) concerning the spoils of war and the obligation of khums (the fifth) for its rightful owners: ... The Imam (peace be upon him) said: As for the spoils [of war], when the Battle of Badr took place, the Prophet (peace be upon him and his family) said: "Whoever kills an enemy shall have such-and-such a reward, and whoever captures a prisoner shall have such-and-such a reward from the spoils of the enemy, for indeed Allah has promised me that I shall be victorious over them and shall gain mastery over their camp." When Allah defeated the polytheists and their possessions were gathered, a man from the Ansar stood up and said: "O Messenger of Allah (peace be upon him and his family)! You commanded us to fight the polytheists and urged us to it, and you promised that whoever captures a prisoner shall have such-and-such from their spoils, and whoever kills someone shall have such-and-such. Now, I have killed two men — I have witnesses to that — and I have also captured a prisoner, and now is the time to fulfil the promise." He sat down, and Sa'd ibn Ubadah [who had been beside the Prophet (peace be upon him and his family) guarding his life and for that reason had not managed to kill or capture anyone] rose and said: "O Messenger of Allah (peace be upon him and his family)! What kept us from killing and capturing was neither fear of the enemy, nor lack of desire for [the reward of] the Hereafter and the spoils [of this world]; we were afraid of leaving you alone — that an army of the polytheists might attack you, or, seeing you alone, might do you harm. If you now give these men what they ask, the rest will have to return empty-handed." Sa'd sat down. Then the Ansari rose again and repeated his first statement and sat down. This exchange was repeated three times. The Prophet (peace be upon him and his family) paid them no attention, and this verse was revealed: يَسْئَلُونَكَ عَنِ الْأَنْفالِ [They ask you about al-anfal (the windfalls)]. Al-anfal is the name for all the possessions that had that day fallen into the hands of the Muslim people, like the other verse [where it is referred to by the name fay'], ما أَفاءَ اللهُ عَلى رَسُولِهِ [What Allah has bestowed upon His Messenger], and the other verse [where it is called ghanimah (spoils)]: أَنَّما غَنِمْتُمْ مِنْ شَيْءٍ [that whatever thing you gain]. Then [in the continuation of the first verse concerning al-anfal] He said: قُلِ الْأَنْفالُ لِلهِ وَ الرَّسُولِ [Say: al-anfal are for Allah and the Messenger]. With this verse Allah removed the spoils entirely from the hands of the soldiers of Islam and assigned them to Allah and His Messenger (peace be upon him and his family) [and so they naturally became part of the public wealth, to be spent under the supervision of the Prophet (peace be upon him and his family) on the interests of Islam and the Muslims]. Then He said: فَاتَّقُوا اللهَ وَ أَصْلِحُوا ذاتَ بَيْنِكُمْ وَ أَطِيعُوا اللهَ وَ رَسُولَهُ إِنْ كُنْتُمْ مُؤْمِنِين [So be careful of (your duty to) Allah, and set aright matters of your difference, and obey Allah and His Messenger if you are believers].