Harsh words can wound just as deeply as swords, and in times of war, they have the power to turn a local dispute into a cruel slaughter. After attempts to appease the tribe of Ephraim with gentle words failed, Jephthah was forced to gather the men of Gilead for a bitter civil war [מלבי״ם]. The crushing blow that the Gileadites eventually delivered was not merely a matter of military necessity. Instead, it was fueled by profound anger over a burning insult that had been hurled at them [מצודת דוד, אברבנאל]. The primary approach among commentators is that the root of this conflict lay in a struggle for status and legitimacy within the broader family of Joseph's tribes. The core of the offense revolved around the accusation that the Gileadites were mere fugitives and leftovers, a status implying that they were lesser, despised, and entirely unimportant [מצודת ציון].
Most commentators understand this insult as a mark of shame directed specifically at the men of Gilead. The members of Ephraim viewed themselves as the heart of the tribe and were furious that the Gileadites had dared to act independently by appointing their own leader. They argued that by choosing to settle across the Jordan River, the Gileadites were essentially deserters who had abandoned their rightful place within the ancestral territories of Ephraim and Manasseh, thereby stripping them of any right to govern [מלבי״ם]. Furthermore, the Ephraimites mocked the Gileadites as fragmented, insignificant refugees trapped between the borders of larger territories, living merely by the grace of the land's true masters [רד״ק, אברבנאל]. This insult was so severe that it implied even the most honorable men of Gilead were inferior to the lowest members of Ephraim [מצודת דוד].
However, a different perspective suggests that the label of being a fugitive did not describe the men of Gilead, but rather the very people hurling the insults. In this view, the mockery came from the lowest and emptiest individuals within the tribe of Ephraim, such as passing shepherds, who would continually belittle the Gileadites and question their worth [רש״י, רד״ק, אברבנאל]. Consequently, the war was fought primarily against these lowly individuals, and the terrible slaughter that ensued served as a hidden punishment for the internal sins of the tribe of Ephraim [רד״ק]. Another angle proposes that the description simply reflected the reality on the ground. Members of Ephraim were staying as refugees within the territories of Manasseh and Gilead, leaving them vulnerable to being overwhelmed by the local population [ביאור שטיינזלץ].
Regarding when these harsh words were actually spoken, some explain that the mockery was an ongoing phenomenon. This constant belittlement provoked the Gileadites to strike out at individual men of Ephraim whenever they passed through their land [רד״ק]. On the other hand, another viewpoint maintains that the arrogant insults were not spoken beforehand, but were instead shouted at the Gileadites in the very heat of battle. It was this specific mid-war insult that drove the men of Gilead to take the extreme measure of capturing the crossings of the Jordan River in order to completely cut off the tribe of Ephraim [אברבנאל].