It is based on the story of General Naaman of Syria who hid his leprosy and covered it up with the mask of his social and professional position.
Naaman would be, for the common person, the very pinnacle of success and everything that anyone could desire. Unfortunately, Naaman was a leper. He was rich, but a rich leper.
It is this image of General Naaman, the secret leper, that the author is dissecting throughout the book. Many people try to stifle their need for God by their worldly privileges, their material goods, their financial empires, and many other things. Despite all that they may be or possess, they are separated from God because of the life of sin.
Reading this book, we discover that one could have the appearance of someone who has succeeded, but all that only at the surface. The sin in your heart smells bad and infects your life.
To remedy this condition, you have to admit who you are - a sinner. If you don't, it is pride, and pride is a mask. It is sad that a vast majority of people in our world still actively wear masks.
Whatever the glaring heights of glory one can scale and attain in this world, you will realise that everything is vanity of vanities. It is, therefore, necessary to obey the requirements of God by acknowledging one's sin, confessing it, receiving forgiveness from Jesus, and surrendering oneself absolutely to the Lord.
