The primary themes of The Great Divorce are moral choice and the absolute disunion of heaven and hell. These themes are developed within a narrative framework provided by an obscure Christian concept, the Refrigerium (the Holiday of the Damned), which includes in Lewis’s version the efforts of the Blessed Spirits to convert those ghosts who have chosen to spend their holiday in the Valley of the Shadow of Life rather than on Earth. The behavior of the ghosts and their encounters with the denizens of heaven unfold the nature of the choices required.
MacDonald’s retrospective interpretation of those choices discloses their transforming quality: For the ghosts who relinquish their hellishness, the grey town will have been purgatory; but those who return to the omnibus will have been in hell both on Earth and in the grey town. Such interpretation emanates from the difference MacDonald perceives between the sequential time humans experience and the eternal present of heaven. As here, logical and temporal contraries of the former become compatible in the latter: Choices become permanent states, past and future become present during Christ’s descent into hell, predestination and freedom of choice become a single verity. The difference between the two time frames is encapsulated in an allegorical image: gigantic forms representing immortal souls stand about a silver table representing time on which chessmen representing humans act out the inmost nature of the souls.
Orthodoxy prevails in the case of the Episcopal Ghost: To be saved, he must repent of his intellectual sins and express belief in the Resurrection, a literal heaven and hell, and the existence of God. Noticeably absent from explicit consideration in The Great Divorce is the fundamental Christian doctrine of faith in Christ as necessary for salvation, much less its formulation by Saint Paul, which so influenced Martin Luther, as justification by faith.