Abdullah bin 'Abdur Rahman al-Daarimi عبد الله بن عبد الرحمن الدارمي · The Book on Military Expeditions

From his father who said: "When the Messenger of Allah (sawS) sent a commander of an army, he would exhort him concerning himself to have Taqwa of Allah, and he would exhort him to be good to those who are with him among the Muslims. He would say: 'Fight in the Name of Allah, in the cause of Allah. Fight those who disbelieve in Allah, and do not steal from the spoils of war or be treacherous, nor mutilate, and…