Question: There is a verse in the Qur’an which stipulates 1/5th of booty from war should be given to Prophet Mohammed (sws). Why? Also, why was the remaining amount distributed among the Muslim warriors? And how are these spoils to be distributed today if the situation arises?
    Answer: The spoils of war obtained in the times of the Prophet (sws) in various battles fought in Arabia were owned by Allah and the Prophet (sws) because of the peculiar nature of these armed offensives.

They ask you about the spoils of war. Say: The spoils belong to Allah and the Prophet. (8:1)

    In these battles, it was the Almighty who, in accordance with a divine law pertaining to his Rusul, had decisively helped the Prophet (sws) and His Companions to overcome the disbelievers. With these spoils, the Prophet (sws), as the head of state, and, as a Rasul, was provided with a way of financial income as well as with money he could spend for the collective welfare of his people. However, since the believers had also assisted in acquiring them by using their personal weapons, camels and horses as well as food, camps and various other items needed during these wars, it was deemed necessary to give them their due from these spoils. Nevertheless, even in these spoils the Qur’an reserved 1/5th of the share for these collective purposes. Consequently while 1/5th share was left at the disposal of the Prophet (sws), the remaining 4/5th was distributed among the fighters:

[You should] know that a fifth of the spoils you get hold of are for Allah and the Prophet and the near relatives and the orphans and the needy and the wayfarer. (8:41)

    Today any course can be adopted in distributing the spoils of war. The above mentioned proportion was specifically meant for the Prophet (sws) since these battles were part of a divine scheme^*.