This is not a blanket-endorsement of C.S. Lewis as a true Christian, of course:
“There are two questions he [the Apologist–CD] will naturally ask himself. (1) Have I been ‘keeping up,’ keeping abreast of recent movements in theology? (2) Have I stood firm (super monstratas vias) amidst all these ‘winds of doctrine’? I want to say emphatically that the second question is far the more important of the two. Our upbringing and the whole atmosphere of the world we live in make it certain that our main temptation will be that of yielding to winds of doctrine, not that of ignoring them. We are not at all likely to be hidebound: we are very likely indeed to be the slaves of fashion. If one has to choose between reading the new books and reading the old, one must choose the old: not because they are necessarily better but because they contain precisely those truths of which our own age is neglectful” (C.S. Lewis, God in the Dock, pp. 91-92).