The Book on Government (Kitab Al-Imara)

Muslim :: Book 20 : Hadith 4690

It has been narrated on the authority of 'Abdullah b. 'Amr that the Messenger of Allah (may peace be upon him) said: A troop of soldiers who fight in tile way of Allah and get their share of the booty receive in advance two-thirds of their reward in the Hereafter and only one-third will remain (to their credit). If they do not receive any booty, they will get their full reward.

Source materials are from the University of Southern California MSA site
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