The English word religion has been around a long time…like, as long as there was English. That’s no surprise, right? And also no surprise is that it has always carried the meaning of “action or conduct indicating belief in and reverence for a divine power one seeks to please” as well as “a life bound by monastic vows.”
What’s interesting is the root of this common word. It comes from Latin, which isn’t surprising either, but while the Latin religionem does indeed mean “respect for what is sacred, reverence for the gods” and so on, Cicero is actually credited with creating this noun from the verb relegere, which literally means “go through it again” or “reread.”
Isn’t that interesting? I’d never thought about it that way, but systems of religion are indeed built on dwelling on thoughts, rereading sacred texts, going through it again and again and again. This is why pretty much every religion on the planet ends up with rites and rituals and creeds, Christianity being no exception. It’s through repetition that we learn a thing and discover its depths.
It’s also worth noting that many later ancients thought religionem was in fact derived from religare, which means “to bind fast.” So though we can, in fact, trace the word to Cicero, that “binding fast” has greatly informed its use and development as well.