Numbers 30:1-9

The reason why I thought that verse 9 has the most bearing on this is because she was a grown woman. She had already left her father's house and so by analogy, she was like a widow or a divorced woman who was living on her own. She was not living in her father's house and she was not a youth. So she was bound by her vow, or as it says, by some agreement in verse 2. And also in verse 3, if a woman vows a vow to the Lord and binds herself by some agreement.

That is what she did. This lady made a contract, a written contract, with these people who took Jessica. Since she was no longer in her father's house, nor was she married yet, she was still a year and a half away from being married. She was not under a man's authority. She would be considered competent to make her own decisions and she would therefore legally have to stand by them. So the contract she signed with the Michigan couple would be legally and eternally binding, and the unmarried father would have no legal recourse in the matter. He is just totally outside the whole case.