Things are going from bad to worse in Israel. Abimelech (chapter 9) was the son of a concubine, but here we have the son of an harlot. God is showing us Israel’s low condition by the weak instruments He uses to help them. And so it is today. God will not use a more refined instrument when Israel is in such a low state. Jephthah seems to be the leader of a rough crowd of men.
V.4-5 Ammon attacks Israel.
V.6-11 Though Jephthah had been a rough man; and although he does make a rash vow (the end of the chapter), in these verses we see the man acting very carefully. He wants to be sure that he has right on his side before he agrees to make a move! It wasn’t just a case of rushing into a war against the Ammonites. Jephthah wanted to be sure that God was behind this move, and that it was for Israel’s good. It is a good thing to remember that if we do things for God in a way which is contrary to His Word, the end will not have God’s blessing. First of all, there must be obedience to His Word.
V.30-40 Jephthah makes a foolish promise to God. He could hardly have expected that a lamb or a goat would come out of his house. We see who came out! We need to be very careful about promises we make to God. God does not ask for payment for the good that He does for us. Jepthah pays for his rash vow.