“Say Shibboleth”
They told him, 'Please say Shibboleth.' If he said, 'Sibboleth,' because he could not pronounce it correctly, they seized him and killed him at the fords of the Jordan. (Judges 12:6 BSB)
What it sounds like today
A strange password test at a river crossing.
The cultural key
A password that cannot be faked because it depends on how you speak, not what you know. The fleeing Ephraimites spoke a dialect that could not produce the 'sh' sound, so when challenged at the Jordan fords to say shibboleth (an ordinary word for a stream or ear of grain), they said Sibboleth and betrayed their origin with a single consonant. It cost 42,000 lives in an inter-tribal slaughter. The episode gave English (and other languages) the word shibboleth for any custom, phrase, or pronunciation that instantly marks a person as inside or outside a group.
Recovered meaning
A civil war turns on a sound: one mispronounced consonant marks a man for death at the river. The scene named a permanent human phenomenon, the small tell that betrays which group you belong to.