These 17 verses are one-third of Jephthah’s story and significant to understanding the man and God’s works.
Jephthah proves himself to be careful and calculating, familiar with the history recorded in the Bible. He stood on facts, exactly where every Christian should also stand.
Early believers didn’t evangelize the known world by expressing opinions, exegeting speculations, or exchanging experiences. They preached historical truth found in the pages of the Bible about who Jesus is, why He came, and what He’d done. We must do no less. We are called to announce the good news of the Saviour who died, was raised to life, and is coming again to judge the living and the dead. To do so, we must know the Bible.

I. Jephthah the Diplomat (Judg 11:12-14). Rather than gather an army, Jephthah sent a diplomatic letter seeking a peaceful settlement rather than war. He asserted himself as an equal to the king, demanding to know why the king of Ammon had his army poised on the eastern border of Israel.
One who wants a fight always finds a reason to fight; the peacemaker tries to avoid a fight (Rom12:18). The Ammonite king called Israel’s territory east of the Jordan River my land.

II. Jephthah the Scholar (Judg 11:15-28). Jephthah gave a three-fold reply: historical (Judg 11:15-22), theological (Judg 11:23-25), and chronological (Judg 11:26).
Jephthah knew the history of his people; he knew the Bible. Moses attempted to lead Israel through the land of Ammon, Moab, Edom, and the Amorites on the way into Canaan. Israel was forced into war with the Amorites, defeated them, and took the land God gifted Israel (Num 20-21; Deut 2:5, 9, 19). Today those who support the Palestinian cause in the land are opposing God’s perpetual land-grant to the Jews.
For 300 years, Israel ruled that land. The Ammonite king claimed ownership over something his people never possessed, and Jephthah knew it! Leadership matters. Israel’s new leader returned history to where it belonged with a focus on God.
The dispute was more than over a piece of ground or history, but who rules over them. Pagans believed their gods were in control over certain territories; the Bible says God rules the whole Earth; every piece and parcel of God’s creation belongs to Him and He gifted a land with borders to Israel (Gen 18:25; Ps 24:1; 136:17-26; 1 Cor 10:26, 28). Jephthah said each place Israel conquered was the Lord’s doing (Judg 11:12, 23, 24) and challenged the Ammonite king that if Chemosh was sovereign over the land, Chemosh could take it back. Jephthah appealed to YHWH, the Judge, to settle the dispute.

III. God the Sovereign Creator (Acts 17:22-31). Under the inspiration of the Holy Spirit, Paul preached that God is the sovereign Creator over His creation (Acts 17:24). He needs nothing from His creatures. He is not dependent upon man, our temples, sacrifices, or worship, but man depends on God (Acts 17:25)!
All humanity is of one blood, we all have a common ancestry in Adam (Acts 17:26). The separation of Earth’s one race into nations and their distinctions is by God. The times and territories of countries is in God’s control (Is 10:12-15; Dan 2:36; Lk 21:24). Even the boundaries of nations have been established by God in relation to His plan for Israel (Deut 32:8).
Both nations and nature give man an opportunity to seek and grope after God, like blind men trying to find something in the dark. As God’s creatures, we instinctively seek/grope for the Creator through creation and conscience (Rom 1:18ff; 2:14-15), but Paul said the days of groping had ended. Since there is one Creator, His creatures must seek after Him (Acts 17:30-31). Now we have the revelation of God in the person of Jesus recorded in the Bible. Scripture is all we need to bring us to faith in Christ and to mature our faith (Rom 1:20-23; 2 Tim 3:16-17).