Numbers 30:2-4

Amplified Bible

² If a man makes a vow to the Lord or swears an oath to bind himself with a pledge [of abstinence], he shall not break (violate, profane) his word; he shall do according to all that proceeds out of his mouth.

³ “Also if a woman makes a vow to the Lord and binds herself by a pledge [of abstinence], while living in her father’s house in her youth, ⁴ and her father hears her vow and her pledge by which she has bound herself, and he offers no objection, then all her vows shall stand and every pledge by which she has bound herself shall stand.