It was narrated from 'Abdullah, who is Ibn Mas'ud, that the Messenger of Allah said: "It is not lawful to shed the blood of a Muslim who bears witness that none has the right to be worshiped but Allah, and that I am the Messenger of Allah, except in one of the three cases: a soul for a soul; a married person who commits adultery, and one who leaves his religion and splits from the Jamaah”.