Numbers 31:26-29
31:26 “You and Eleazar the priest, and all the family leaders of the community, take the sum of the plunder that was captured, both people and animals.
31:27 Divide the plunder into two parts, one for those who took part in the war – who went out to battle – and the other for all the community.
31:28 “You must exact a tribute for the Lord from the fighting men who went out to battle: one life out of five hundred, from the people, the cattle, and from the donkeys and the sheep.
31:29 You are to take it from their half-share and give it to Eleazar the priest for a raised offering to the Lord.