Abu Umamah ibn Sahl ibn Hunayf reported that Sayyidina Uthman ibn Affan (who was locked up in his home for fear of those who wrought mischief) climbed up the roof top one day. He asked the besiegers, “I adjure you by Allah, do you know that Allah’s Messenger (SAW) said: The blood of a Muslim is forbidden except for one of three crimes. (They are :) adultery committed by a married person, apostatizing after joining Islam, slaying someone without just cause. He is killed for these things. By Allah, I have not committed adultery either in jahilyah or after Islam. I have not apostatized since having sworn allegiance to Allah’s Messenger (SAW). And, I have not slain any soul who Allah has made sacred. Then why do you slay me?
[Muslim 1672]
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