Religion is a social phenomenon, a category-concept that includes many practices that differ widely from one another, though some are so similar that they can be grouped together as a single system of belief. Typically, people who practice a particular religion share similar beliefs and follow common rituals.
These commonalities are a source of the distinctiveness and importance of religion. They may also explain why religious communities resist the challenges of scientific research, philosophical criticism and other threats to their faith.
A few scholars use a substantive definition of religion, determining that something is a religion if it involves belief in a distinctive kind of reality. This approach, however, is not without its problems, and it does not seem to capture the full scope of what religions are all about.
Other scholars take a functional definition of religion, determining that something is religious if it has the power to unify a community or provide direction in life. This is the approach of Emile Durkheim, Clifford Geertz and others, and it has a lot to recommend it.
The trouble, again, is that it does not clearly differentiate between phenomena that would fit the functional definition and those that do not. In addition, this approach tends to treat religion as a universal feature of human culture, which is arguably an exaggeration of what we know about the origin of religions.
Whether we take a functional or substantive definition, the defining features of religions seem to be that they make people feel special and important, that they are part of a moral community that binds individuals to one another, that they are based on a worldview and that they have a sanctifying effect.
As a result, there are no clear boundaries between religious and non-religious systems of belief, and even the most secular of contemporary society can be said to possess some religious elements. These include feelings of spiritual well-being, the desire for moral guidance and the wish to give oneself meaning and purpose in a chaotic, indifferent universe.
In fact, this last function explains why many people today cling to their religious beliefs, despite the overwhelming evidence that religions are false and harmful. Even in modern, rich democracies where established churches are under threat from new forms of social organization and technological innovation, people still find comfort in the idea that their personal piety will protect them from economic instability and other sources of anxiety. It is not unreasonable to assume that this desire will continue, and perhaps accelerate, if the pandemic brings more economic uncertainty and feelings of hopelessness. If so, religious authority will have to reinvent itself, and quickly, or face extinction. If it does, the resurgence of religion may help to mitigate the effects of globalization and terrorism. If not, the schism between church and state will widen further and the world will become more divided.