Apart from a few thousand Hindus and Sikhs and a few hundred Jews, all Afghans are Muslims. Eighty per cent of these are Sunni of the Hanafite rite, and the rest are Shiʿa of the Jaffarite rite, with a small Ismaʿili minority of one to two hundred thousand people. In a country like Afghanistan, where the concept of the nation has developed but recently, where the state is seen as external to society and where people's allegiance is directed primarily towards their local community, the only thing which all Afghans have in common is Islam.

Afghan peasant life is permeated by religion. It provides the intellectual horizon, the system of values and the code of behaviour, even though occasionally this may involve a clash with other codes of conduct, such as the tribal system; it provides the only source of legitimation based upon universal values. Nevertheless, the social basis of this religion varies according to whether the context within which it exists is tribal or non-tribal, rural or urban, and in the same way the link between ideology and religion varies according to whether a group is secularised or fundamentalist, traditionalist or reformist. Thus one finds different forms of religious expression, each with its own dynamic and symbolism.