Richter 12:5

When the Gileadites had beaten the Ephraimites, they took the fords of the Jordan before the Ephraimites (or towards Ephraim: see Jdg 3:28; Jdg 7:24), to cut off their retreat and prevent their return to their homes. And "when fugitives of Ephraim wanted to cross, the men of Gilead asked them, Art thou Ephrathi," i.e., an Ephraimite? And if he said no, they made him pronounce the word Shibboleth (a stream or flood, as in Psa 69:3, Psa 69:16; not an ear of corn, which is quite unsuitable here); "and if he said, Sibboleth, not taking care to pronounce it correctly, they laid hold of him and put him to death at the fords of the Jordan." In this manner there fell at that time, i.e., during the whole war, 42,000 Ephraimites. The "fugitives of Ephraim" were the Ephraimites who had escaped from the battle and wished to return home. The expression is used here in its ordinary sense, and not with the contemptuous sense in which the Ephraimites had used it in Jdg 12:4. From this history we learn quite casually that the Ephraimites generally pronounced sh (shin) like s (samech). הכין is used elliptically for לב הכין, to direct his heart to anything, pay heed (compare Sa1 23:22; Ch1 28:2, with Ch2 12:14; Ch2 30:19).

In this chapter we have, I. Jephthah's rencounter with the Ephraimites, and the blood shed on that unhappy occasion (Jdg 12:1-6), and the conclusion of Jephthah's life and government (Jdg 12:7). II. A short account of three other of the judges of Israel: Ibzan (Jdg 12:8-10), Elon (Jdg 12:11, Jdg 12:12), Abdon (Jdg 12:13-15).