Linguistics
The Bible's shibboleth test: one mispronounced word marked you for death
In the Book of Judges, Gileadite fighters guarding the Jordan's fords made anyone crossing say 'shibboleth.' Fleeing Ephraimites, whose dialect lacked the 'sh' sound, could only manage 'sibboleth' — and were killed on the spot. Scholars call it the first recorded use of a pronunciation test as a password, and the word now means any phrase that marks who belongs to a group.