Numbers 30:2

2 aIf a man vows a vow to the Lord, or bswears an oath to bind himself by a pledge, he shall not break his word. cHe shall do according to all that proceeds out of his mouth.

Deuteronomy 23:21

21 d“If you make a vow to the Lord your God, you shall not delay fulfilling it, for the Lord your God will surely require it of you, and you will be guilty of sin.
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