Most people are deluded by this, having convinced themselves that their persona ("mask," "false self") is a manifestation of their inner person. Occasionally, the smiley mask or confident mask or hard mask slips off, and there is a moment of rage or weakness or tenderness. At that moment we have a window into the heart, a glimpse of who that person really is. What is in the heart is the person's "normal"; the mask is the person's "false normal."
C.S. Lewis shows us how this can work in an opposite way. He writes:
"We imply, and often believe, that habitual vices are exceptional single acts, and make the opposite mistake about our virtues - like the bad tennis player who calls his normal form his "bad days" and mistakes his rare successes for his normal. I do not think it is our fault that we cannot tell the real truth about ourselves; the persistent, life-long, inner murmur of spite, jealousy, prurience, greed and self-complacence, simply will not go into words. But the important thing is that we should not mistake our inevitably limited utterances for a full account of the worst that is inside." (The Problem of Pain, 53-54)
We have two untruthul situations.
1. Wearing the false-self mask to hide who we really are.
2. Mistaking a rare spiritual or moral success for who we really are.
Think of yourself as a patient in the doctor's office. You smile and say "Everything's fine," but the doctor says "Let's take the MRI to make sure." Or, you say "I felt great for an hour yesterday!" The doctor says, "Let's take the MRI to make sure." We may be afraid to know the truth of our physical condition, but I hope you will agree with me that we need to know it, and it will be best for us to get it treated.
Who are you, really? God knows, surely. Make it your habit to enter God's office regularly. Sit before God and pray, "Search me, O God, and know my heart; test me and know my anxious thoughts. See if there is any offensive way in me, and lead me in the way everlasting." (Psalm 139:23-24) God will show you the truth about your real self, and begin restoring your heart (removing layers of veneer to get at the original finish) and then transforming it (meta-morphing it; changing its form into Christelikeness).
If you can relate to 1 and 2 above, then you have a morally and spiritually diseased heart. The good news is that you don't have to have this kind of heart disease. Be searched-out by God and allow him to restore and transform your heart into a new, clean heart.
