In Judges 11 Jephthah leads God’s people into battle against an enemy and makes a promise to God in doing so: “If you will give the Ammonites into my hand, then whatever comes out from the doors of my house to meet me when I return in peace from the Ammonites shall be the Lord’s, and I will offer it up for a burnt offering” (Judges 11:30-31).
Now, of course, sacrifices were pretty custom for the time. My guess is he was most likely trying to one-up a normal sacrifice to honor God for a victory. Rather than just sacrifice any given farm animal, he would sacrifice one of great meaning to him—like a dog or a cat—something from inside the house.
But if you know the story, then you know that what comes out of the house is not a dog or a cat—it’s his daughter. His only child comes bursting out the front door, dancing with tambourine in hand, celebrating her father’s victory. Now this is where most of us say, “Oh, sorry God, you know that’s not what I meant. I’m not going to sacrifice my child, of course.” But in this case, bad theology leads to a stupid God-dishonoring decision. Jephthah must have looked at the world around him where child sacrifice was not unheard of and thought to himself, I will have to make the same great sacrifice to my God.
Now if he knew the Old Testament law, he would have been made aware of the fact that God hates child sacrifice and expressly forbids it (Deuteronomy 12:31; 18:9-12). But it seems Jephthah doesn’t know good theology and therefore goes on to commit an incredibly heinous sin while thinking it’s an honorable form of worship. Even his daughter thought it was the right thing to be done to her, despite the fact that God had already illustrated with Abraham and Isaac that he is different from the false gods and would never have anyone sacrifice their children.
Bad theology is dangerous and it still kills, even today. And because the Bible writers sometimes document stories like that of Jephthah exactly as they happened, without commentary, we sometimes get confused. Other times we even get inspired by these stories because we read them the wrong way. We need to understand that this matter-of-fact story was not a positive one and we need to know God’s character and the Bible well enough to discern its negative tone. This, again, is why we must read the Bible while sitting next to Jesus.