The concepts of allegory and irony had originally a philosophical and theological rather than literary meaning. To understand how these two concepts were transferred from Antiquity to the Middle Ages, we have to consider the notion of translatio studii. The most important channels through which knowledge of classical concepts was disseminated in the Middle Ages were texts of the classical rhetorical tradition, derivative compilations of early medieval authorities, oral instruction provided by the monastic schools and rhetorical manuals composed in the twelfth and thirteenth centuries. Translation studies ensured that medieval theory and literature adopted classical philosophy and rhetoric, classical hermeneutics combined with Christian theology. The concept of allegory relied, at least in medieval secular literature, more strongly on the classical sources than the concept of irony, which had freed itself from ancient concepts. Medieval literature is saturated with allegories, but its definitions are usually associated with narratives, whereas medieval irony distinguishes itself as a specific mode of thought.