Exodus 20:7

"You shall not take the name of the LORD your God in vain, for the LORD will not hold him guiltless who takes His name in vain.

Surrounding context

20:6 but showing mercy to thousands, to those who love Me and keep My commandments.

20:7 "You shall not take the name of the LORD your God in vain, for the LORD will not hold him guiltless who takes His name in vain.

20:8 "Remember the Sabbath day, to keep it holy.