Deuteronomy 5:11 in the King James Version
Thou shalt not take the name of the LORD thy God in vain: for the LORD will not hold him guiltless that taketh his name in vain.
Context
10 and showing loving kindness to thousands of those who love me and keep my commandments.
11 “You shall not misuse the name of the LORD your God; for the LORD will not hold him guiltless who misuses his name.
12 “Observe the Sabbath day, to keep it holy, as the LORD your God commanded you.