You shall not take the Name of Hashem, your G-d, in vain, for Hashem will not absolve anyone who takes His Name in vain. (Exodus 20:7)
Leviticus 19:12 You shall not swear falsely by My Name, thereby desecrating the Name of your G-d--I Am Hashem.
Leviticus 22:32-33 You shall not desecrate My Holy Name, rather I should be sanctified among the children of Israel; I Am Hashem Who Sanctifies you, Who Took you out of the land of egypt to be a G-d unto you; I Am Hashem.
What is it to take the Name of G-d in vain? The word "vain" can be defined in two ways--for no reason or for personal reasons, and these are both the same--for both are to no avail and spread only corruption. The Hebrew word "LaShav" is translated as "in vain." The Hebrew word also has two meanings. It can be read as "for no reason" which is "to no avail," or as "falsely" in order to "promote a falsehood." The Commandment not to take the Name of G-d in vain, means both these things. It is Forbidden to use the Name of G-d to no avail, for no good Reason, as it is Forbidden to speak falsely in G-d's Name. To act this way is a form of idolatry; stealing the identity of G-d and replacing Him with your own thoughts. And "Hashem will not absolve anyone who takes His Name in vain," for these people are guilty and will suffer for their crimes; they will not be absolved by claiming to speak in the Name of G-d. In fact, they will be guilty, for this is a crime in itself--desecrating the Name of G-d--and they will suffer for their crimes, as Justice will be served.
But a person takes the Name of G-d in vain in order justify his corruption. Therefore, this sin goes along with an act of corruption--and he will be punished according to his deeds, according to the Laws of G-d. But should a person take the Name of G-d in vain in order to lead Israel astray, in defiance of G-d, the Judge of Israel, that person will die according the Judgement that applies for idolaters, as a consequence of his rebelliousness.