It is established in the books of heresiography (books detailing the doctrines of the sects) that the central, core, uniting element of all the sects of the Khārijites, is the issue rebelling against the rulers on grounds of perceived or actual injustice or what they consider to be disbelief, but which is not disbelief. Rather it is something that is perfectly lawful in Islām (such as treaties with non-Muslims, giving them gifts, having trade and diplomatic relations or legislating in affairs of broad public interest to achieve the objectives of the Sharīʿah such as border controls, highway regulations and so on) or it is a sin that does not reach the level of disbelief. So this is what unites all Khārijites.

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