This is not a blanket-endorsement or agreement with everything Chesterton writes. And since Chesterton was a Roman Catholic he obviously was not a true Christian.
“There is a quality needed today for the spread of all truth, and especially religious truth, which is very simple and vivid, but which I find it very difficult to fit with a word. So many words have become catchwords. I suppose that our critics, in their learned way, would have recourse to the little-known Greek word paradox, if I were simply to say that they are not quite broad-minded enough to be Catholics. In their own jargon, being broad-minded so often means being blankminded.
If I were to say they suffer from a lack of imagination, they might suppose (heaven help them) that I meant that what we believe is all imaginary. Nor indeed do either of these two terms define the definite thing I intend. It would be nearer the mark if I said that they cannot see all round a subject; or that they cannot see anything against the backdrop of everything else.
The learned man, of what I may call the Cambridge type, is like a man who should spend years in making a minute ordnance map of the country between Cork and Dublin, and never discover that Ireland is an island. It is not a question of understanding something difficult. It is rather a question of opening the mind wide enough to understand something easy [The efficacious atonement of Jesus Christ as the very heart, the very life-blood of the gospel?–CD]. It is not to be attained by years of labour; it is more likely to be attained in a moment of laziness [the “laziness” of regeneration?–CD]; when the map-maker who has long been poring over the map with his nose close to Cork, may lean back for a moment and suddenly see Ireland. It is much more difficult to get such men to lean back for a moment and see Christendom” (G.K. Chesterton, The Common Man, p. 233).