Where does the word "religion" come from?

The English word religion arrived from Old French in the 1200s and goes back to the Latin religio. But the Romans did not mean what we mean. In classical Latin, religio was a sense of duty or conscientiousness, a scruple, the feeling of being bound to do something properly. Romans used it most often in everyday situations: hesitation, caution, even anxiety. Where religio itself comes from is, honestly, uncertain.

The Romans themselves argued about it. Cicero said it came from relegere, "to go over again": a religious person was someone who carefully went back over every detail of the rites. Centuries later, the Christian writer Lactantius, followed by Augustine, proposed religare, "to bind again", a tie between people and God. Both stories are still repeated, and neither can be proven.

Cicero also had a story for its opposite. People who spent whole days praying and sacrificing so their children would outlive them were called superstitious, from superstes, a survivor.

The biggest surprise is how young our idea of religion is. When the word entered English, it meant life under monastic vows. The idea of religion as a separate box, distinct from ordinary life, only appeared in the 1500s. The Bible and the Quran have no word for it in their original languages, and the names Buddhism and Hinduism only entered English in the 18th and 19th centuries.