Commanding Right and Forbidding Wrong in Islamic Thought

What kind of duty do we have to try to stop other people doing wrong? The question is intelligible in just about any culture, but few of them seek to answer it in a rigourous fashion. The most striking exception is found in the Islamic tradition, where 'commanding right' and 'forbidding wrong' is a central moral tenet already mentioned in the Koran. As an historian of Islam whose research has rang...