Salman bin Buraidah narrated from his father Sayyiduna Buraidah (may Allah be pleased with him): He said: Whenever the Messenger of Allah (peace and blessings be upon him) appointed a commander over a detachment, he would advise him to “adopt the fear of Allah himself and to treat the Muslims who are with him well, fearing Allah regarding them.” He (peace and blessings be upon him) would also say: “Fight in the name of Allah, in the way of Allah, fight those who disbelieve in Allah. Fight, but do not be treacherous, do not act dishonestly, do not mutilate, and do not kill a child.”
To cut off the nose, ears, heart, liver, hands, and feet separately is called "muthlah" (mutilation).
From this hadith, the legitimacy of military expeditions is established, and it is also proven that giving advice at the time of departure is recommended. Furthermore, it is established that the commander and the combatants should adopt piety (taqwa) and sincerity (ikhlas) on the path of jihad, and the Messenger of Allah (sallallahu alayhi wa sallam) has instructed to avoid breach of trust, treachery, and betrayal. He also forbade, in a state of excitement or anger, the desecration of the dead, i.e., mutilation (muthlah), and the killing of minor children. In other ahadith, women and the elderly are also added to this prohibition.
These are the golden principles of warfare in Islam, which demonstrate that Islam is a moderate and realistic religion.