The will of mankind is either presumptuous or despairing. No human creature can satisfy the law.
 Martin Luther, Table Talk (1566). copy citation

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

Context

“even as it was with Peter, when he swore he would lay down his life for Christ. I will not lie or dissemble before my God, but will freely confess, I am not able to effect that good which I intend, but await the happy hour when God shall be pleased to meet me with his grace. The will of mankind is either presumptuous or despairing. No human creature can satisfy the law. For the law of God discourses with me, as it were, after this manner: Here is a great, a high, and a steep mountain, and thou must go over it; whereupon my flesh and free-will say, I will go over it;” source