Redefining War

The Prophet (peace be upon him) has altered the standards and aims of pre-Islamic wars. The pre-Islamic wars were nothing more than robbing, killing, plundering, tyranny and aggression-oriented wars. Those wars focused on winning victory, oppressing the weak people and demolishing their houses and constructions. For them, war was a means by which they could rape or unveil women, practice cruelty against the weak elders, children and the babies, and spoil tillage and animals, and spread corruption on the Earth.

War in Islam is a Jihad for the purification of the land of Allah from deception, treachery, sinful deeds, cruelty, oppression and aggression. It is a sacred war that aims at spreading security, safety, mercy and compassion as well as observation of rights and fairness. Allah's Messenger issued honourable and strict rules about war and ordered his soldiers and leaders to obey them. They were forbidden from breaking those rules under any circumstances. Whenever Allah's Messenger appointed a leader for an army or a battalion, he used to say to him: "Let your invasion be in the Name of Allah and for His sake. Fight those who disbelieve in Allah. Invade but do not plunder nor conceal booty. Never deform the corpse of a dead person or kill an infant child."

Allah's Messenger asked people to facilitate but he forbade them to bear down hard on others or constrain. "Pacify", he said, "and do not punish." When it happened that he arrived at the battlefield at night, he would never invade the enemy till it was morning. He utterly forbade burning (i.e. torturing people) in fire, killing children and women or even beating them. He also forbade theft and robbery and proceeded so far as to say gains acquired through plundering are not less forbidden than the flesh of a corpse. Corruption of tillage, killing of the animals and cutting down of trees were all forbidden unless they were badly needed and there was no other substitute. He said: "Do not kill a wounded person nor run after a fleeing one or kill a captive." He decreed that envoys cannot be killed. He also strictly prohibited the killing of those who made covenants. He even said: "Whoever kills one who is under pledge to a covenant, shall not smell paradise, though its smell could be experienced at a forty-year distance from it."

Source:
"The Sealed Nectar" - Safi-ur-Rahman Al-Mubarakpuri, pp. 514-516