Jephthah is not considered an especially outstanding man, not in Torah wisdom and not as a public leader. The sages list him as one of the "minor people" of the world, whose lack of seriousness cost him the life of his daughter. He collects empty people around him, and he is banned from his own family (Judges 11:3). However, when he comes to rescue the nation of Israel he performs as a gifted leader who is aware of the moral advantage his people have over the claims of the enemy, as can be seen in the way he argues with the king of the Children of Ammon. Jephthah understands that victory in war is assured only for people who are infused with knowledge of the justice of their position, and he therefore takes the time to summarize the claims of Israel in front of the whole world before he goes into battle.
Here are a number of lessons that can be learned from his claims.
The first claim is the legal one. "Israel did not take the land of Moab or the land of the Children of Ammon" [11:15]. A similar event took place in our generation when Arab leaders asked to meet with Rav Tzvi Yehuda Kook in an effort to promote better understanding between Jews and Arabs. As a prior condition before meeting, Rav Kook insisted that they sign a document that they are aware that we did not take anything from any Arab government that ruled in the land, but rather that we took the land from the British, who got it from the Turks. Only after the Arab leaders signed did Rav Kook agree to meet with them. The lesson to be learned is that no agreement can lead to real peace if it is based on denial of the true facts.
The second claim is that the land was obtained as a result of a war of defense: "Sihon did not allow Israel to pass through his borders. And Sichon gathered his nation and camped in Jahaz, and they fought against Israel. And the G-d of Israel gave over Sihon and his whole nation into the hands of Israel, and they struck them. And Israel took possession of the whole land of the Amorites, who dwelt in that land." [11:20-21].
The third claim invokes Divine guidance, which operates through historic events. "And now, the G-d of Israel has sent away the Amorites because of the Children of Israel, do you want to take possession now?" [11:23]. Today, we are in the process of taking possession of the land as part of a Divine plan for "tikun" - mending the faults of the world through the actions of the Children of Israel.
The fourth claim is that the enemy is not telling the truth. Previously the land belonged to Moab and not to Ammon. "You will get possession of whatever your god Chemosh gives you" [11:24]. But, as is well known, Chemosh is the god of Moab and not the god of Ammon! Today also, fairly recent immigrants make claims of ownership of the land in the name of ancient nations which no longer exist.
The fifth claim is that even Balak, who was indeed from Moab, never tried to take the area away from Israel, because of its superior morality, which was even recognized by Balaam: "Are you any better than Balak son of Zippor?" [11:25].
The sixth claim is that the place has already been filled with a large area of settlement. "Israel has been dwelling there... for three hundred years" [11:26]. The same is true of our situation today.
The seventh claim is that Israel did not attack the Amorites: "I have not sinned against you!" [11:27].
Source: “NOTES FROM THE HAFTARAH” – a biweekly column in Shabbat B’Shabbato (Zomet Institute) See: http://www.zomet.org.il/eng – Chukat 5776, issue 1631.