This essay explores Charles Williams’s use of the Arthurian myth to sustain a religious worldview in the aftermath of sustained attacks on the relevance and veracity of Christian belief in the early twentieth century. The premise to be explored is that key developments in science and philosophy made during the nineteenth and early twentieth centuries resulted in a cultural and intellectual milieu in which assertions of religious faith became increasingly difficult. In literary terms this became evident in, amongst other things, the significant reduction in the production of devotional poetry. By the late 1930s the intellectual environment was such that Charles Williams, a man of profound religious belief who might otherwise have been expected to produce devotional work, turned to a much older mode, that of myth, that had taken on new relevance in the modern world. Williams’s use of this mode allowed him the possibility of expressing a singularly Christian vision to a world in which such vision was in danger of becoming anathema. This essay examines the way in which Williams’s lexis, verse structure, and narrative mode builds on his Arthurian source material to allow for an appreciation of religiously-informed ideas in the modern world.