The present study aims to analyze, from a specific standpoint, The Pilgrim s Regress (1933), first fiction book by the Irish writer C. S. Lewis (1898-1963). This work is often related to the author s conversion experience to Christianity, and this study aims further interpretations beyond mere allegorical autobiography. One of its objectives is to show how Lewis writes his obscure allegory within an important debate about the nature of language, after the World War I (1914-18). Then, the author presents, in his narrative, ideas which are commonly expressed inside scholarly discussions in Oxford and Cambridge and scarcely noted by the unwary reader. One of the most important post-war aspects was exactly the shift on how to understand language. Although there was no sophisticated media as the World War II s – television, or radio for instance – newspapers, books, pamphlets, images and songs were used to convey war propaganda, in the WWI. Therefore, the idea behind a combat fought not only with arms but also trough language took place among those who lived that period in time and who decided to study it. Certainly, many questions could be raised about language objectivity as source of reliable information and its use in the context of literature, when the underlying dangers of such way to handle language is exposed. In The Pilgrim’s Regress one could see the author positioning himself before this controversy about the nature of language, situated between WWI and WWII.