“And you shall not swear falsely in My Name” (Vayikra 19:12)
It is a negative commandment that one must not swear falsely, as it says “And you shall not swear falsely in My Name”. This prohibition concerns a spoken oath, and is broken down into four parts, two of which concern the future and two of which concern the past. The two about the past are: swearing that a certain thing was done (when it was not done) and swearing that something was not done (when it was). The two concerning the future are: swearing that in the future he will do something (and in the end he does not do it) and swearing that he will not do something (and he then does it).
This prohibition applies in all places and at all times, to men and women. One who deliberately transgresses this prohibition, if he has been warned and there are witnesses, receives lashes. If it was not deliberate, he must bring an Oleh Veyored offering (an offering whose type depends on his financial circumstances).