Narrated Aishah, Ummul Muminin: The Messenger of Allah صلی اللہ علیہ وسلم Said: The blood of a Muslim man who testifies that there is no god but Allah and that Muhammad is Allah's Messenger should not lawfully be shed except only for one of three reasons: a man who committed fornication after marriage, in which case he should be stoned; one who goes forth to fight with Allah and His Messenger, in which case he should be killed or crucified or exiled from the land; or one who commits murder for which he is killed.

Abdullah (bin Masud) reported the Messenger of Allah صلی اللہ علیہ وسلم as saying: The blood of a Muslim man who testifies that there is no god but Allah and that I am the Messenger of Allah should not be lawfully shed but only for one of three reasons: married fornicator, soul for soul, and one who deserts his religion separating himself from the community.

Narrated Abu Umamah ibn Sahl: We were with Uthman when he was besieged in the house. There was an entrance to the house. He who entered it heard the speech of those who were in the Bilat. Uthman then entered it. He came out to us, looking pale. He said: They are threatening to kill me now. We said: Allah will be sufficient for you against them, Commander of the Faithful! He asked: Why kill me? I heard the Messenger of Allah صلی اللہ علیہ وسلم say: It is not lawful to kill a man who is a Muslim except for one of the three reasons: Kufr (disbelief) after accepting Islam, fornication after marriage, or wrongfully killing someone, for which he may be killed. I swear by Allah, I have not committed fornication before or after the coming of Islam, nor did I ever want another religion for me instead of my religion since Allah gave guidance to me, nor have I killed anyone. So for what reason do you want to kill me? Abu Dawud said: Uthman and Abu Bakr (Allah be pleased with them) abandoned drinking wine in pre-Islamic times.