by Karen » March 1st, 2006, 12:26 pm
It's a security measure, to make sure you know who is friend and who is foe. The reference is Biblical, and is known as a shibboleth:
Judges 12:5-6 The Gileadites captured the fords of the Jordan leading to Ephraim, and whenever a survivor of Ephraim said, "Let me cross over," the men of Gilead asked him, "Are you an Ephraimite?" If he replied, "No," they said, "All right, say 'Shibboleth.' " He said, "Sibboleth," because he could not pronounce the word correctly, they seized him and killed him at the fords of the Jordan. Forty-two thousand Ephraimites were killed at that time.
Perhaps the most well-known example of this was in WWII when the Americans were fighting the Japanese. Since Japanese people have difficulty pronouncing the letter "l", passwords were usually something like "lollapalooza", which only American soldiers could say correctly.
I have always imagined that paradise will be a kind of library. -- Jorge Luis Borges