Judges 11:27 - Joseph Benson’s Commentary on the Old and New Testaments

Wherefore I have not sinned I have done thee no wrong. The Lord, the Judge, be judge Let him determine this controversy by the success of this day and war. The meaning is, that if they were not moved by these reasons, but the controversy must be decided by arms, he committed his cause to God, the righteous Judge of the whole world, who, he doubted not, would do him right. Be judge this day He does not mean that God would determine the right by giving him the victory then, when he spake these words, (for he was not yet ready to give them battle,) but that God would judge of the justice of his present plea, and accordingly give sentence when the matter came to be tried in battle. There cannot be a finer picture of justice, candour, fair reasoning, moderation, and unwillingness to proceed to the dreadful miseries of war, joined with a noble spirit to defend his country in its just rights, than that which Jephthah shows in his messages to the Ammonites. It were to be wished that all kings would follow his steps, and not rush into the shocking inhumanities and miseries of war with too much precipitation, but first try what good temper, moderation, fair reasoning, and a claim to no more than their just rights, will do with their enemies.