What does Judges 12:3 mean?

Jephthah continues to defend his actions to the men of Ephraim. He rejects their claim that they were not asked to come and fight with Gilead against the Ammonites (Judges 12:1–2). Jephthah insists that Gilead did call for help from Ephraim while Gilead was being oppressed (Judges 10:17–18; 11:4). The Ephraimites did not cross over the Jordan to save Gilead. Only now, after the battle, are they arriving to complain about not being involved in the fight.

When he realized Ephraim was not coming to save him, Jephthah risked his own life and acted alone. Then the Lord subjected the Ammonites to defeat. Here, again, Jephthah describes everything happening to Gilead in personal terms (Judges 11:12, 27). He speaks as the one under attack, the one who struck back, and the one who gained the victory. Commentators take this in one of several ways. One option is that Jephthah is completely self-focused; he really thinks everything happening is all about him. The other option is that he so thoroughly identifies with his people that he sees their suffering and victory as his own. Another possibility is that Jephthah is speaking as a head-of-state, rather than as an individual.

After pointing out that Ephraim had opportunities to fight, if they really wanted to, Jephthah asks for the real reason behind their aggression. It's a good question, but it gets no clear answer. Based on the taunts of the Ephraimites in the following verse (Judges 12:4), some commentators speculate Ephraim wanted to claim Gilead as their own. Whatever their true motives, the men of Ephraim have come ready for battle, and don't seem interested in being pacified.