When you shall vow a vow unto the LORD your God, you shall not delay to pay it: for the LORD your God will surely require it of you; and it would be sin to you.
That which is gone out from your lips you shall keep and perform; even a freewill offering, according as you have vowed unto the LORD your God, which you have promised with your mouth.
And the children of Israel struck them not, because the leaders of the congregation had sworn to them by the LORD God of Israel. And all the congregation murmured against the leaders.