Numbers

If a man vow a vow unto the Lord, or swear an oath to bind his soul with a bond; he shall not break his word, he shall do according to all that proceedeth out of his mouth.

And she vowed a vow, and said, O Lord of hosts, if thou wilt indeed look on the affliction of thine handmaid, and remember me, and not forget thine handmaid, but wilt give unto thine handmaid a man child, then I will give him unto the Lord all the days of his life, and there shall no razor come upon his head.

Speak unto the children of Israel, and say unto them, When a man shall make a singular vow, the persons shall be for the Lord by thy estimation.