The sins of the flesh are bad, but they are the least bad of all sins.
 C. S. Lewis, Mere Christianity (1952). copy citation

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Author C. S. Lewis
Source Mere Christianity
Topic sin flesh
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

“Finally, though I have had to speak at some length about sex, I want to make it as clear as I possibly can that the centre of Christian morality is not here. If anyone thinks that Christians regard unchastity as the supreme vice, he is quite wrong. The sins of the flesh are bad, but they are the least bad of all sins. All the worst pleasures are purely spiritual: the pleasure of putting other people in the wrong, of bossing and patronising and spoiling sport, and back-biting, the pleasures of power, of hatred. For there are two things inside me, competing with the human self which I must try to become.” source