This sermon study begins with reflections about Newman’s frame of mind at the time of his thirteenth University Sermon—“Implicit and Explicit Reason” (1840). For Newman, the time was the beginning of an intellectual and spiritual conversion, while the sermon itself described the powerful interplay of reason and faith in Christian believers and presented the rudiments of an epistemology that would later influencehis An Essay in Aid of a Grammar of Assent (1870).