1 Samuel 30:20-25

So David had captured all the sheep and the cattle which the people drove ahead of the other livestock, and they said, “This is David’s spoil.” When David came to the two hundred men who were too exhausted to follow David, who had also been left at the brook Besor, and they went out to meet David and to meet the people who were with him, then David approached the people and greeted them. Then all the wicked and worthless men among those who went with David said, “Because they did not go with us, we will not give them any of the spoil that we have recovered, except to every man his wife and his children, that they may lead them away and depart.” Then David said, “You must not do so, my brothers, with what the LORD has given us, who has kept us and delivered into our hand the band that came against us. And who will listen to you in this matter? For as his share is who goes down to the battle, so shall his share be who stays by the baggage; they shall share alike.” So it has been from that day forward, that he made it a statute and an ordinance for Israel to this day.