Lewis is subtle about revealing the manner in which his theological ideas significantly diverge from the Roman Catholics and the Protestants around him. Much of his theological thought is expressed in allegories and fantasy rather than in religious exposition. Morevoer, even in his religious works, he wrote in a colloquial style, avoiding the terminology and jargon of theologians which would be a dead give-away for his unconventional theology. His work was not to destroy the false, except as it came in the way of building the true. Therefore Lewis sought to speak only what he believed, saying little concerning what he did not believe; trusting in the true to cast out the false, and shunning dispute. But a close reader who is familiar with the fault lines of theological debate will distinctly perceive from what Lewis says and leaves unsaid that Lewis was much more sympathetic to Orthodox theology than he was to standard Catholic and Protestant theology.

In particular, in ''Mere Christianity'', Lewis emphasizes the Orthodox "Christus Victor" model of Christ's work to the exclusion of the Roman Catholic model which holds that Christ was "penalized" by God in our place. In that book, Lewis also emphasizes the Orthodox "theosis" understanding of salvation to the exclusion of the Roman Catholic thought that salvation includes being "pardoned," "justified" or "forgiven" by God. Finally, Lewis did not believe in a penal hell, choosing instead the Orthodox understanding that "hell" is the piercing and terrifying experience of Divine Love by a person who did not develop the capacity to love on earth, regardless of their formal religious affiliation as a Christian or otherwise (see ''The Great Divorce'' and ''The Last Battle''). In short, Lewis was a universalist in the way that Orthodox Christianity teaches universalism, believing that God loves all his creatures now and throughout eternity, and we experience "hell" only insofar as, and so long as, we choose not to conform ourselves to Divine Love. Like the Orthodox, Lewis believed that we could repent beyond the grave and we could all legitimately expect (but not predict with certainty) apokatastasis, universal reconciliation of humanity to divine goodness (see ''The Great Divorce''). A brilliant article on this matter is is [http://scholar.lib.vt.edu/theses/available/etd-05292002-153921/unrestricted/etd.pdf Reason, Imagination, and Universalism in C. S. Lewis]