Acts by which people willfully deceive are introduced by al-Ghazzali along with the degrees of hypocrisy, a discussion of hidden hypocrisy, the type of hypocrisy which nullifies good deeds, and teh treatment of a spiritual heart sick with the disease of hypocrisy. He then describes acts of devotion which are permitted to be revealed, the sins which are permitted to be concealed and the permission to in some cases refrain from charitable acts out of fear of hypocrisy. This is Book XXVIII of Part Three of the Alchemy of Happiness entitled The Destroyers.