Do not swear an oath of expression over falsehood.
“Do not swear falsely by My name” Vayikra 19:12
This is called an oath of expression.
A person is punishable if he takes this oath over things that it is possible to do, whether in the future or the past.
“that I ate “or “I threw a stone into the sea “or “this person spoke with that person “or
“that I did not eat “or that “I did not throw the stone into the sea” or “this person did not speak to that person”
Regarding the future for example - “that I shall eat “or “I shall not eat” or
“that I shall throw a stone into the sea “or “I will not throw…”
If a person swore regarding any of these statements he violates this prohibition.
This applies in all places at all times for men and women.