What is the ruling concerning those who openly declare a ruling contrary to established authority, such as 'No judgment except for Allah'?
General Chapter
Al-Mughni
Book of Fighting Rebellious Groups
Primary text
Ali ibn Abi Talib responded to such a declaration by stating it was 'a true word intended for falsehood.' He established a covenant that they would not be prevented from mosques where Allah's name is mentioned, nor from the public treasury (fay') as long as they maintained peace, and that the Muslims would not initiate fighting against them. Evidence for this lenient approach is found in the Prophet's interaction with the man who questioned him, where Khalid requested permission to execute him, but the Prophet refused, stating, 'Perhaps he prays,' and clarifying, 'I was not commanded to probe into the hearts of people.'
Supporting text
The practice of Ali, supported by the report of Umar ibn Abd al-Aziz responding to a letter regarding the Khawarij insulting him, dictates that if they only insult, they may be insulted in return or pardoned; but if they draw weapons, they should be fought back against, and if they strike, they may be struck. This is further supported by the Prophet not confronting the hypocrites present with him in Medina.