This is from Mere Christianity of all books. In context (I'm not even quoting the whole sentence, much less the whole paragraph) Lewis is making the pretty common observation that the default Christian political approach is socioeconomically to the left but socioculturally to the right of generalized secular liberalism. Out of context, though, it sounds like something you'd read in a tractate by some based-in-more-ways-than-one Bolivian village curate.
From what I remember, he calls the 'sociocultural' aspect old-fashioned, even for the time he was writing. My take is that I think it was a tacit admission that such an approach (biblically based, or otherwise) or an emphasis on this being 'real' Christianity was effectively impossible in an industrial society. But at the same time, redistributionist leftism or welfarism as he knew it was structurally impossible
then (time of Jesus etc) but was possible at the time he wrote and indeed was being implemented at the time the book was collected.
What thoughts he may have had on the later British 1950's sociocultural conservative 'redoubt' (that has unwound and took religious observance with it) at the time of the greatest strength of the welfare state, I have no idea.
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