But if you should be unwilling to vow, it is not sin in you.
LXX
Deuteronomy 23:22
And if thou wilt vow a vow to the Lord thy God, thou shalt not delay to pay it; for the Lord thy God will surely require it of thee, and [otherwise] it shall be sin in thee.
Parallel Translations
But if thou shalt forbear to vow, it shall be no sin in thee.
But if you refrain from making a vow, it shall be no sin in you.