Religion is, in the broadest sense of the word, any system connected with spiritual and supernatural components that impacts an individual’s worldview, behavior, morality, culture, and approach to certain writings, persons, or places. It is also commonly defined as a group of beliefs about a supreme being or gods, as well as an individual’s relationship with the cosmos, human society, and their own self.

In the broadest sense of the term, many people consider themselves to be religious. They may be atheists, agnostics, or believers in one of the “world’s” major religions such as Christianity, Islam, Hinduism, or Buddhism. They might follow an indigenous faith, or a religion that is regionally specific such as the Yoruba or Cherokee. They might follow a folk religion, or even a superstition such as the belief in witchcraft.

While the concept is remarkably broad, scholars have narrowed its definition over time. It is most often used today to refer to a set of social practices that can be found in every culture, though some scholars take the more narrow sense of the word that includes only those that share the same beliefs and rituals. Still others use the word to refer to a particular function that religion performs in human life, and they treat the phenomenon as something inevitable.

Some sociologists, most notably Karl Marx, Emile Durkheim, and Max Weber, analyzed the influence of religion in society. They argued that religion served to reinforce existing patterns of stratification and inequality in a given culture. The theorists who viewed religion in this light were called the sociologists of religion.

Since these early attempts at understanding the nature of religion, a great deal of theory has been accumulated. Among the problems with some of this theory is that it makes the assumption that there are essential features common to all religions, and therefore that there is a single defining property that can be applied to any religion. While it is important to know how different religions operate in their own context, this kind of a priori theory is illegitimate for the study of religion (see Theory, anthropological).

Other scholars have been able to recognize that a definition of religion must be sufficiently flexible so as to allow room for diverse interpretations and experiences. This flexibility has made it possible to avoid a reduction of the concept to a lowest common denominator, or to a concept that can only be applied to a small slice of the material. In the last several decades, scholars influenced by the work of Continental philosophers such as Friedrich Nietzsche and Michel Foucault have been growing more aware that our concepts create boundaries that reflect the ideological power structures which they reinforce. The challenge is to avoid imposing such boundaries on the study of religion. In this way, we will be able to make the most of its unique contribution to human life. This article is based on the entry for Religion in the Oxford English Dictionary.