The Devil is the very spirit of misery. He is the origin of depression and the ‘sickness unto death’. Luther himself suffered frequently and for extended periods from depression, and thus had occasion to develop a thorough knowledge of psychology. He describes depression in language so firmly based in experience that it bridges the centuries and makes us forget the gulf that separates us from him. When he speaks of getting up in the morning only to have the day stretch out endlessly before him, when