Numbers 31:27

and divide the prey into two parts; between them that took the war upon them, who assumed the offensive, made the attack, who went out to battle, and between all the congregation. The army received half the spoil, as having been actively engaged in the arduous campaign, but the congregation was also fairly entitled to its share, a rule which was observed also in later times, Joshua 22:8; 1 Samuel 30:24.