Religious/spiritual belief systems and practices adapt as people’s needs change. They evolve within a culture and often across cultures and early human species as well, sometimes at a faster pace than other social institutions such as law and economics but more frequently at a slower pace mixing existing features with new ones.
As the semantic range of what is said to be a religion has expanded, so too have questions about how it is best defined. In particular, some scholars (especially those influenced by Foucauldian or post-colonial theory) have argued that the concept of religion is itself deeply implicated in western statism and imperialism and that it is inappropriate to critique individual beliefs and behaviors or other practices that self-describe as religious.
Others, however, have taken a more cautious approach to the definition of religion, seeking to delimit it in a way that is not merely arbitrary but that is informed by a variety of scholarly disciplines, most notably anthropology, history, philosophy, and religious studies. This approach has tended to focus on the use of rituals and rules that have an ethical dimension in defining what is considered sacred or moral.
The most comprehensive and widely used definition of religion is that of American anthropologist Clifford Geertz, who argues that a religion is “a system of signs that establishes powerful, pervasive moods and motivations by clothing conceptions of a general order of existence in such an aura of factuality that they become irresistible to men.” This functional definition drops the substantive element and instead defines religion as whatever systems of belief and practice bring together people into moral communities whether or not those systems involve belief in unusual realities.