Deuteronomy 23:21

19 Do not charge your brother interest on money, food, or any other type of loan.

20 You may charge a foreigner interest, but not your brother, so that the LORD your God may bless you in everything to which you put your hand in the land that you are entering to possess.

If you make a vow to the LORD your God, do not be slow to keep it, because He will surely require it of you, and you will be guilty of sin.

22 But if you refrain from making a vow, you will not be guilty of sin.

23 Be careful to follow through on what comes from your lips, because you have freely vowed to the LORD your God with your own mouth.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB
If you make a vow to the LORD your God, do not be slow to keep it, because He will surely require it of you, and you will be guilty of sin.
KJV
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.
WEB
When you vow a vow to the LORD your God, you shall not be slack to pay it, for the LORD your God will surely require it of you; and it would be sin in you.
ASV
When thou shalt vow a vow unto Jehovah thy God, thou shalt not be slack to pay it: for Jehovah thy God will surely require it of thee; and it would be sin in thee.
DARBY
When thou vowest a vow to Jehovah thy God, thou shalt not delay to perform it; for Jehovah thy God will certainly require it of thee, and it shall be sin in thee.
BLB
When you make a vow to YHWH your God, you shall not delay to pay it. For YHWH your God will surely require it of you, and it would be sin in you.
ÅB
Når du gjør Herren din Gud et løfte, da skal du ikke vente med å holde det; for Herren din Gud vil kreve det av deg, og du vil få synd på deg.
OTB
Hvis du gir et løfte til Herren din Gud, må du ikke nøle med å oppfylle det, for Herren din Gud vil sikkert kreve det av deg, og du vil være skyldig i synd.
B1930
Når du gjør Herren din Gud et løfte, da skal du ikke vente med å holde det; for Herren din Gud vil kreve det av dig, og du vil få synd på dig.

Study notes (Tyndale)

Original text and word study

Cross references