The thing about lies is that we don't know they are lies.  But for many of us, a lie is the center of our deepest beliefs: BE-LIE-VE.  This is critical because our beliefs drive our behavior.  Jesus offers us a solution: truth.  He tells us that if we abide in His word, we are truly is disciples.  In this we find that the key to identifying a lie is by abiding in the truth.