We learn, on the one hand, that we cannot trust ourselves even in our best moments, and, on the other, that we need not despair even in our worst, for our failures are forgiven. The only fatal thing is to sit down content with anything less than perfection.
 C. S. Lewis, Mere Christianity (1952). copy citation

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Author C. S. Lewis
Source Mere Christianity
Topic perfection failure
Date 1952
Language English
Reference
Note Adapted from a series of BBC radio talks made between 1942 and 1944
Weblink https://www.dacc.edu/assets/pdfs/PCM/merechristianitylewis.pdf

Context

“(or courage, or truthfulness, or any other virtue) may be, this process trains us in habits of the soul which are more important still. It cures our illusions about ourselves and teaches us to depend on God. We learn, on the one hand, that we cannot trust ourselves even in our best moments, and, on the other, that we need not despair even in our worst, for our failures are forgiven. The only fatal thing is to sit down content with anything less than perfection. Thirdly, people often misunderstand what psychology teaches about ‘repressions’. It teaches us that ‘repressed’ sex is dangerous. But ‘repressed’ is here a technical term: it does not mean ‘suppressed’ in the sense of ‘denied’ or ‘resisted’.” source