Faced with a tense confrontation, Gideon chooses a path of humility and diplomacy to calm the brewing conflict with the tribe of Ephraim. He intentionally magnifies their role in the recent victory while downplaying his own achievements. He points out that even though the men of Ephraim did not join the fight at the very beginning of the war, their ultimate success was far greater than anything he accomplished [ביאור שטיינזלץ]. The capture of the Midianite princes was an act of such immense bravery that the victory is recognized as a direct result of God delivering the enemy into their hands [מלבי״ם].
To further soothe their pride, Gideon lowers himself by rhetorically questioning his own abilities in comparison to theirs. He wonders aloud if he could have ever matched their heroic deeds or reached their level of success [מצודת דוד, ביאור שטיינזלץ]. He openly admits that his own actions carry far less importance than theirs [רש״י], confessing that he simply lacked the capability to achieve what they had done [מלבי״ם].
This deeply respectful approach has an immediate effect. The intense anger and emotional storm that had gripped the men of Ephraim quickly fade [רד״ק, מצודת ציון, ביאור שטיינזלץ]. The primary approach among commentators is that as soon as Gideon spoke to their hearts, openly acknowledging their superior strength and crucial victory, their minds were put at ease. Their fierce rage dissolved, and their anger toward him disappeared entirely.