A good bit of Lewis’s success can, I think, be attributed to the fact that he actually writes relatively little “theology” in this technical sense. Clearly, he’s read a good bit of it and been instructed by it—he does not in any sense belittle it—but he tends to seek language that captures and communicates the quality, the feel, of living and thinking as a Christian. As Austin Farrer put it: “[Lewis’] real power was not proof; it was depiction. There lived in his writings a Christian universe that could be both thought and felt, in which he was at home and in which he made his reader feel at home.” That is the universe I want to explore. It illumines the everyday, so that we may find in it shafts of the divine glory that point to God, so that we may sense the eternal significance of ordinary life.
https://www.firstthings.com/article/1998/08/the-everyday-cs-lewis
Acerbity [əˈsɜːbɪtɪ] 