When Jephthah returned home after slaughtering the Ammonites, his daughter came out to meet him.
Jephthah came to Mizpeh unto his house, and, behold, his daughter came out to meet him with timbrels and with dances. Judges 11.34When Jephthah saw his daughter, he tore his clothes and told her that he had opened his mouth to God.
When he saw her, that he rent his clothes, and said, Alas, my daughter … for I have opened my mouth unto the LORD, and I cannot go back. 11.35His daughter (who is unnamed in the Bible) said,
My father, if thou hast opened thy mouth unto the LORD, do to me according to that which hath proceeded out of thy mouth. 11.36What had proceeded out of Jephthah’s mouth was, of course, a God-inspired promise to God to kill whatever greeted him. And so by God, that's what he did. A man's got to do what a man's got to do.
And ... her father ... did with her according to his vow which he had vowed. 11.39God inspired Jephthah to make the vow, so he expected him to abide by it. And God was so pleased when Jephthah killed his daughter for him that he decided to kill his own son for you.
But I'll save that story for later.
God's next killing: 42,000 killed for failing the "Shibboleth" test