Like many Christian writers, Lewis associates the state of Christianity with light. To be a good, pious Christian, is to “see the world for the first time,” illuminated by the light of faith and salvation. Thus, light represents the inner peace, joy, and profound wisdom that the worship of Jesus Christ affords the human race.
Light Quotes in Mere Christianity
Atheism turns out to be too simple. If the whole universe has no meaning, we should never have found out that it has no meaning: just as, if there were no light in the universe and therefore no creatures with eyes, we should never know it was dark. Dark would be a word without meaning.
Imagine a lot of people who have always lived in the dark. You come and try to describe to them what light is like. You might tell them that if they come into the light that same light would fall on them all and they would all reflect it and thus become what we call visible. Is it not quite possible that they would imagine that, since they were all receiving the same light, and all reacting to it in the same way (i.e. all reflecting it), they would all look alike? Whereas you and I know that the light will in fact bring out, or show up, how different they are.