A man must as vehemently strive against such cogitations as against unbelief, despair, heresies, and such like temptations.
 Martin Luther, Table Talk (1566). copy citation

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Author Martin Luther
Source Table Talk
Topic temptation despair
Date 1566
Language English
Reference
Note Translated by William Hazlitt
Weblink http://www.ntslibrary.com/PDF%20Books/Luther%20Table%20Talk.pdf

Context

“when we have done this, we may well consider whether it is expedient to trouble oneself about impossible things, though it is a very difficult thing to expel such thoughts, so fiercely drives the devil. A man must as vehemently strive against such cogitations as against unbelief, despair, heresies, and such like temptations. For most of us are deceived herewith, not believing they proceed from the devil, who yet himself fell through those very cogitations, assuming to be equal with the Most Highest, and to know all that God knows, and scorning to know what he ought to know, and what was needful for him.” source