Having been humbled by the Law, and having been brought to a right estimate of himself, a man will repent. He finds out that he is so depraved, that no strength, no works, no merits of his own will ever deliver him from his guilt.
 Martin Luther, Commentary on the Epistle to the Galatians (1535). copy citation

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Author Martin Luther
Source Commentary on the Epistle to the Galatians
Topic guilt strength
Date 1535
Language English
Reference
Note Translated by Theodore Graebner
Weblink http://www.gutenberg.org/files/1549/1549-h/1549-h.htm

Context

“In contrast to the doting dreams of the scholastics, we teach this: First a person must learn to know himself from the Law. With the prophet he will then confess: "All have sinned, and come short of the glory of God." And, "there is none that doeth good, no, not one." And, "against thee, thee only, have I sinned."
Having been humbled by the Law, and having been brought to a right estimate of himself, a man will repent. He finds out that he is so depraved, that no strength, no works, no merits of his own will ever deliver him from his guilt. He will then understand the meaning of Paul's words: "I am sold under sin"; and "they are all under sin."
At this state a person begins to lament: "Who is going to help me?" In due time comes the Word of the Gospel, and says: "Son, thy sins are forgiven thee.” source