Mazza, Enrico. "Chapter Eleven: The Early Middle Ages." The Celebration of the Eucharist: The Origin of the Rite and the Development of Its Interpretation. Collegeville, MN: The Liturgical Press/Pueblo, 1999, 161-197.
After the fourth century, Mazza finds a gradual move away from understanding the eucharist in terms of typology. Interpretation rather moved toward either "the figural method…(or) the method of sacramental realism" (Mazza 1999, 161). The figural method arose after typology had changed into allegory. The figure of the allegory was understood as the important element in eucharistic understanding. The method of sacramental realism, as we saw in chapter ten, allowed for a typological understanding, but one which may have been considered less important than the emphasis on the real belief in what the sacrament contained (Mazza 1999, 162). This interpretation grew into a philosophy per se.
Mazza considers Amalarius of Metz (ca. 770/75-850/53) as the fundamental pioneer in medieval eucharistic theology related to the sacrifice of Christ, specifically in allegorical terms (Mazza 1999, 162ff). His work seeks out the origin and the nature of individual rites and their relationships to salvation (Mazza 1999, 163). His commentaries take an allegorical approach throughout. For instance, because "the Mass is the celebration of the passion of Christ, each of the rites making up the Eucharist must represent a stage in that passion" (Mazza 1999, 164). Mazza describes the steps of this process in some detail, as the method of interpretation is less commonly used today.
Amalarius approaches his understanding of the rites of the church through the context of allegory, allowing various elements of his allegorical interpretation to represent different things at different times. In all, he is concerned with the allegory, not with arguments for or descriptions of sacramentality (Mazza 1999, 169). Amalarius was eventually condemned as a heretic, with charges of "having destroyed the unity of the body of Christ" based on comments made pertaining to the fraction of the bread (Mazza 1999, 171). Mazza considers there to have been political motivations behind the prosecution as well.
After the time of Amalarius, Mazza notes that a number of commentaries on the mass were produced prior to the close of the 13th century (Mazza 1999, 173). Mazza reviews a number of these; particularly works of the 12th century. Much of the work is influenced by Amalarius, whether by spurring agreement or inciting rejection of his allegorical principles.
While the discussion around the eucharist was largely focused on allegorical interpretations, Mazza notes that the eucharistic realism, discussed in the context of the fourth century, was not developed in any of the extant treatises (Mazza 1999, 182). While there was a clear concept of realism (Christ's body becomes bread), it was not questioned. Rather, Mazza finds the realism to serve as one of the normal theological presuppositions. The tenets do show up in some theological treatises (as opposed to commentaries on the liturgy). Mazza reviews in particular the work of Paschasius Radbert (fl. ca. 830), who takes the bread to change in a physical way into the body of Christ; and his colleague Ratramnus, who takes the change to be figural and non-physical in nature (Mazza 1999, 186). From this foundation, theological investigations moved along with the task of describing specifically what happens during the eucharistic ritual (Mazza 1999, 187ff). At issue is what results in creating union with Christ, and in how that union with Christ is described. There is a difficulty especially involving a distinction between physical and spiritual eating and drinking (Mazza 1999, 189). In the eleventh century this issue came to a head with the work of Berengarius, who was hesitant to acknowledge the presence of the body and blood of Chrsit in a "sensible" manner as opposed to being present "sacramentally" (Mazza 1999, 190). Berengarius was considered heretical because he may have been interpreted as rejecting a bodily presence of Christ. Mazza finds that Berengarius can not be proven to hold to the heretical views ascribed to him.
The Middle Ages also saw developments in terms of eucharistic devotion, in which Christians would particularly emphasize their commitment to particular elements of the eucharistic rite (Mazza 1999, 192). While Mazza finds eucharistic devotion as early as the patristic period, at that time the devotion was focused on a Christological view of the divinity of Jesus. In the Middle Ages, he finds it more governed by Christ's humanity and our emotive responses (Mazza 1999, 192). Among the elements of this new devotion were moves to kiss the wounds on a crucifix (Mazza 1999, 194), and to catch a glimpse of the body and blood of Christ in the elevation (Mazza 1999, 196). Dramatization of the events around Christ's ministry were part of the natural outcome of this fervor.