“The deceitfulness of the heart of man appears in no one thing so much as this of spiritual pride and self-righteousness. The subtlety of Satan appears in its height, in his managing persons with respect to this sin. And perhaps one reason may be that here he has most experience; he knows the way of its coming in; he is acquainted with the secret springs of it: it was his own sin. Experience gives vast advantage in leading souls, either in good or evil.”