What is the ruling on those who hold extreme views, such as declaring a Muslim who committed a major sin an apostate, if they do not engage in open revolt?
General Chapter
Al-Mughni
Book of Fighting Rebellious Groups
Primary text
If they express such views but have not left the authority of the Imam or shed forbidden blood, they are treated as Muslims regarding liability for life and property. If they insult the ruler, they receive discretionary punishment (ta'zir).
Supporting text
Those who maintain the view of their apostasy imply that they must first repent, and if they do not, they are executed for their disbelief, like an apostate. The evidence cited for this extreme view is the Prophet's saying: "Wherever you meet them, fight them," and his statement regarding a man who questioned his division of spoils: "Go and kill him," which was directed at someone like the Khawarij.