The Third Commandment
3. Thou shalt not not take the name of the Lord thy God in vain.
The above is a traditional shortened verbiage for the 3rd Commandment.
The actual text from Exodus 20:7 (NKJV) is:
“You shall not tkae the name of the Lord your God in vain, for the Lord will not hold him guiltless who takes His name in vain.”