Honesty is always the best policy!
Make a conscious decision to always speak the truth.
Do you like being lied to?
Treat others the way you want treated
not how they treat you.
One chooses to lie or not.
There is never any reason to lie, always speak the turth, always.
However!
Never, never lie, always be honest and truthful, but that doesn't mean you can't omit facts if it becomes life threateningly necessary.
As an example -
A man breaks into your home points a gun to your head and asks if anyone else is in the house.
Honest and truthful answer is "How can I be alone if you are here with me?"
You need not tell him that someone else is there, because you just did, he is there. The omittion of the fact that someone you care about is also there does not create a lie, white or other wise. Always speak the truth and you won't have to remember anything, nor worry about being found out.
When faced with those who lie and can't be trusted to tell the truth just walk away. Put them out your gate., that is the only way to teach them.
