Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) said: "The blood of a Muslim who professes 'La ilaha illallah (Muhammadur Rasulullah)' is not lawful, except in three cases: a life for a life, a married person who commits adultery, and one who leaves the religion and separates from the community (apostate)."