Deuteronomy 23:21

23:21 When you shall vow a vow to Yahweh your God, you shall not be slack to pay it: for Yahweh your God will surely require it of you; and it would be sin in you.
-World English Bible

Other Translation

23:21 When thou shalt vow a vow unto the LORD thy God, thou shalt not slack to pay it: for the LORD thy God will surely require it of thee; and it would be sin in thee.
-King James Version