Berceo's Sacrificio de la misa: The First Spanish Liturgical Textbook

Critics have traditionally looked to the Fourth Lateran Council of 1215 as the origin of the doctrine of transubstantiation and the inspiration for Gonzalo de Berceo's Sacrificio de la misa. Textual evidence proves that this belief far predated 1215 and that Berceo based his text on the Latin tradition of explicating the Mass that had become common in the eleventh and twelfth centuries. Due to the unwillingness of Spanish prelates to institute ecclesiastic reforms, it is likely that Berceo had not read the constitutions of Lateran IV before writing the Sacrificio. Rather than a text that reflects Berceo's pious devotion or a desire to participate in the Lateran reforms, internal evidence shows that the intended readership of the text must have been students preparing for ordination or priests requiring additional instruction. As a guide to the Mass and its symbolism, Berceo's Sacrificio is not only the first explanation of liturgy in a Romance language but also a textbook in verse that parallels the types of texts used by theology students in the centuries leading up to Berceo's time.