Deuteronomy 23:21

21 a“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.

Deuteronomy 23:23

23You shall be careful to do what has passed your lips, for you have voluntarily vowed to the Lord your God what you have promised with your mouth.

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