It is narrated from Hazrat Uqbah bin Malik (may Allah be pleased with him) that one day a detachment attacked the people of a certain area in the morning; those people lived near water. One of them came out, so a Muslim attacked him and said, "I am a Muslim," but despite this, he killed him. On their return, when they informed the Prophet (peace and blessings be upon him) about this, the Prophet (peace and blessings be upon him) stood up to deliver a sermon, praised Allah, and after saying 'Amma ba'd', said: "What is the matter that a Muslim kills another person even after he has professed Islam?" That person said, "O Messenger of Allah! He only recited the Kalimah to save his life." The Prophet (peace and blessings be upon him) turned his face away from him and, raising his right hand, said three times: "Allah has refused to accept my word in favor of one who kills a Muslim."