Judges 12:2-6

So Jephthah said to them, “I and my people were in a major dispute with the sons of Ammon; and I did call you, but you did not save me from their hand.

When I saw that you were no deliverer, I took my life in my hands and crossed over against the sons of Ammon, and the Lord handed them over to me. Why then have you come up to me this day to fight against me?”

Then Jephthah gathered all the men of Gilead and fought Ephraim; and the men of Gilead defeated Ephraim, because they said, “You are survivors of Ephraim, you Gileadites, in the midst of Ephraim and in the midst of Manasseh.”

And the Gileadites took control of the crossing places of the Jordan opposite Ephraim. And it happened whenever any of the survivors of Ephraim said, “Let me cross over,” that the men of Gilead would say to him, “Are you an Ephraimite?” If he said, “No,”

then they would say to him, “Just say, ‘Shibboleth.’ ” But he said, “Sibboleth,” for he was not prepared to pronounce it correctly. Then they seized him and slaughtered him at the crossing places of the Jordan. So at that time forty-two thousand from Ephraim fell.