Judges 12:5-6

Gilead captured the fords of the Jordan at the crossing to Ephraim. If an Ephraimite fugitive said, “Let me cross,” the men of Gilead would ask, “Are you an Ephraimite?” and he would say, “No.” And they would say, “Say, ‘Shibboleth.’” But he would always say, “Sibboleth”—he couldn’t say it right. Then they would grab him and kill him there at the fords of the Jordan. Forty-two Ephraimite divisions were killed on that occasion.