New American Standard Bible (©1995)
"You shall be careful to perform what goes out from your lips, just as you have voluntarily vowed to the LORD your God, what you have promised.
King James Bible
That which is gone out of thy lips thou shalt keep and perform; even a freewill offering, according as thou hast vowed unto the LORD thy God, which thou hast promised with thy mouth.
Darby Bible Translation
What is gone out of thy lips thou shalt keep and do, as thou hast vowed to Jehovah thy God, the voluntary-offering that thou hast promised with thy mouth.
English Revised Version
That which is gone out of thy lips thou shalt observe and do; according as thou hast vowed unto the LORD thy God, a freewill offering, which thou hast promised with thy mouth.
Online Parallel Bible