Throughout “The Book of Sand,” Borges questions the role of literature in perceiving and understanding reality and the spiritual role that literature plays in religion and dogma. The narrator owns multiple Bibles and holds strong opinions on their relative quality, while the salesman is a Presbyterian who sells Bibles. The Bible has served as a guide for millions of Christians who consider it a sacred text that guides their lives. In some ways, the Book of Sand serves as a counterpoint to the Bible in the story, pointing to and exposing flaws in the connection between literature and spirituality while highlighting the power of literature.

This theme emerges early in the text when the narrator mentions his prized possession, a Wycliffe Bible from the 14th century. John Wycliffe and this translation of the Bible into English notably inspired Lollardy, which was a movement similar in many ways to Protestantism in that it advocated for reform of the Catholic Church. Lollardy, in fact, was viewed as heresy, just as Protestantism would later be considered heresy by Catholics. By valuing the Wycliffe Bible so highly, Borges’s narrator draws attention to his own heretical standpoint, which is further revealed as he trades in the supposed heresy of the Wycliffe text for the heresy of the Book of Sand, which the salesman calls ”diabolic.