No person has ever sunk so low that he cannot rise again. On the other hand, no man's standing is so secure that he may not fall.
 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
Date 1535
Language English
Reference
Note Translated by Theodore Graebner
Weblink http://www.gutenberg.org/files/1549/1549-h/1549-h.htm

Context

“Job and Jeremiah cursed the day of their birth. Elijah and Jonah became weary of life and prayed for death. Such offenses on the part of the saints, the Scriptures record for the comfort of those who are near despair. No person has ever sunk so low that he cannot rise again. On the other hand, no man's standing is so secure that he may not fall. If Peter fell, I may fall. If he rose again, I may rise again. We have the same gifts that they had, the same Christ, the same baptism and the same Gospel, the same forgiveness of sins. They needed these saving ordinances just as much as we do.” source