سنن النسائي

Abu Umamah bin Sahl and 'Abdullah bin 'Amir bin Rabi'ah said: "We were with 'Uthman when he was under siege and we could hear what was said from Al-Balat. 'Uthman came in one day, then he came out, and said: 'They are threatening to kill me.' We said: 'Allah will suffice you against them.' He said: 'Why would they kill me? I heard the Messenger of Allah (ﷺ) [SAW] say: It is not permissible to shed the blood of a Muslim except in one of three cases: A man who reverts to Kufr after becoming Muslim, or commits adultery after being married, or one who kills a soul unlawfully. By Allah, I did not commit adultery during Jahiliyyah or in Islam, I never wished to follow any other religion since Allah guided me, and I have never killed anyone, so why do they want to kill me?'"