Numbers 30:2

2 `When a man voweth a vow to Jehovah, or hath sworn an oath to bind a bond on his soul, he doth not pollute his word; according to all that is going out from his mouth he doth.

Numbers 30:2 In-Context

1 And Moses speaketh unto the heads of the tribes of the sons of Israel, saying, `This [is] the thing which Jehovah hath commanded:
2 `When a man voweth a vow to Jehovah, or hath sworn an oath to bind a bond on his soul, he doth not pollute his word; according to all that is going out from his mouth he doth.
3 `And when a woman voweth a vow to Jehovah, and hath bound a bond in the house of her father in her youth,
4 and her father hath heard her vow, and her bond which she hath bound on her soul, and her father hath kept silent at her, then have all her vows been established, and every bond which she hath bound on her soul is established.
5 `And if her father hath disallowed her in the day of his hearing, none of her vows and her bonds which she hath bound on her soul is established, and Jehovah is propitious to her, for her father hath disallowed her.
Young's Literal Translation is in the public domain.