`Uthman bin 'Affan looked at them when they spoke of killing. He said: “Are they threatening to kill me? Why would they kill me? I heard the Messenger of Allah (ﷺ) say: “It is not lawful to shed the blood of a Muslim except in one of three (cases): a man who commits adultery when he is a married person, then he should be stoned; a man who kills a soul not in retaliation for murder; and a man who apostatizes after becoming Muslim.' By Allah (SWT), I never committed adultery either during Ignorance days nor in Islam, and I have never killed a Muslim soul, and I have not apostatized since I became Muslim.”
“It is not lawful to shed the blood of a Muslim who bears witness that none has the right to be worshiped but Allah (SWT), and that I am the Messenger of Allah (ﷺ), except in one of three cases: a soul for a soul; a married person who commits adultery, and one who leaves his religion and splits from the Jama`ah.”
“Allah (SWT) will not accept any good deed from a polytheist who committed polytheism after having become Muslim, until he leaves the polytheists and joins the Muslims.”
“Carrying out one of the legal punishments prescribed by Allah (SWT) is better than if it were to rain for forty nights in the land of Allah (SWT), Glorified is He.”
“Whoever denies a Verse of the Qur'an, it is permissible to strike his neck (i.e., execute him) Whoever says, Lailaha illallahu wahduhu la sharika lahu, wa anna Muhammadan `abduhu wa rasuluhu (None has the right to be worshiped but Allah (SWT) alone, and Muhammad (ﷺ) is His slave and Messenger), no one has any was of harming him, unless he (does something which) deserves a legal punishment, and it is carried out on him.”
“I heard 'Atiyyah Al-Quradhi say: 'We were presented to the Messenger of Allah (ﷺ) on the Day of Quraidhah. Those whose pubic hair had grown were killed, and those whose pubic hair had not yet grown were let go. I was one of those whose pubic hair had not yet grown, so I was let go.”