God's Spirit then clothed Jephthah guaranteeing divine enablement and victory in the approaching encounter with the Ammonite army (v. 29; cf. 3:10; 6:34; 14:6, 19; 1 Sam. 10:10). He travelled through Gilead in the tribal territory of Gad and eastern Manasseh to the north recruiting soldiers. He led his troops back to Mizpah in Gilead (cf. v. 11) and then eastward into Ammon.
Jephthah made a vow before going into battle. He promised that if the Lord would give him victory he would give God whatever came out of the door of his house when he returned from the conflict (vv. 30-31). He would offer this person or animal either as a sacrifice of dedication to the Lord or as a burnt offering of worship (v. 31). The masculine gender of the Hebrew word translated "whatever"can apply to a person or an animal, but he was probably thinking of an animal.
"His negotiations with the elders, his diplomacy with the Ammonites, and his vow, have all amply displayed Jephthah's facility with words. Jephthah, we know, is goodat opening his mouth. (How ironical that his name means literally he opens'!). What has precipitated the crisis with his daughter is that he has opened his mouth to Yahweh, that is, he has tried to conduct his relationship with God in the same way that he has conducted his relationships with men. He has debased religion (a vow, an offering) into politics."224
Webb pointed out in the helpful article quoted above that Israel had done the same thing Jephthah did. This tendency to negotiate with God marked and marred her relationship with Yahweh during this period of her history.
The Lord gave Jephthah success in the battle, and he destroyed 20 cities in Ammon. He broke the Ammonites' strong power, so they ceased oppressing Israel (v. 33).
Note the chiastic structure of verses 29-32. This section begins and ends with the promise and fulfillment of God's giving Jephthah victory. When the Spirit came on him there was no doubt that he would defeat the enemy. The center of the chiasm relates Jephthah's bargaining with God to insure victory. He did not need to make this vow. He had already testified that God had given His people victory in the past (vv. 21, 24). Apparently his faith was not as strong as it might have been, and this weakness led him to seek a guarantee of success by making the vow.
Jephthah's vow reveals that he had a rather unenlightened concept of Yahweh. His commitment to the Lord was strangely strong, but his understanding of God was not Scriptural. He did not know what the Law revealed about Yahweh, or he had forgotten this. His concept of God bears the marks of Canaanite influence. His belief that he needed to bargain with and bribe God to get Him to bless His people was unfortunate (cf. Jer. 29:11). He also believed that Yahweh took pleasure in what hurts people, that He is sadistic. This idea was also inaccurate and pagan. Furthermore he believed that God might abandon him before he finished his battle. God had promised that He would not do this as long as His people trusted and obeyed Him (Deut. 28:1, 7). Jephthah made his tragic vow because he did not have a Scriptural view of God.225He should have vowed to offer the inhabitants of the cities he would conquer as sacrifices to God (Num. 21:2).
The secret to Jephthah's success was his essential trust in and obedience to Yahweh. This is always the key to spiritual success. His life teaches us that God can and does use people with all types of backgrounds. God does not produce His instruments with a cookie cutter. Each one is different. He even uses people whom others reject because of their families and lifestyles. He prepares His tools throughout their lives and uses everything in their backgrounds to equip them to conduct a unique ministry for Himself.
