Written as a dissertation under the direction of Marina Münkler, Felix Prautzsch's book examines encounters between Christians and non-Christians, or more specifically between Christian saints and their “heathen” opponents, in Latin and German hagiographic narratives produced in the thirteenth century. Prautzsch's argument is primarily formal, utilizing systems theory grounded in the work of Niklas Luhmann to analyze the structures through which legenda constructed and communicated meaning. However, Prautzsch also historically situates these texts in relation to the crusades, the rise of the mendicant orders, the missionary activity of Franciscans to North Africa and Asia, and related phenomena that increased the scope of possibility for actual encounters between Christians and non-Christians to a degree parallel to the situation of early Christians as a persecuted minority in the pagan Roman Empire.

The theoretical and historical frameworks are outlined in the first two chapters, while the remainder of the book focuses on structural and literary analysis of specific hagiographic texts. These include several selections from Jacobus da Voragine's Legenda Aurea and the Middle High German Passional associated with the Teutonic Order, and a range of other legends in German verse such as Wetzel von Bernau's Margaretenlegende, Reinbot von Durne's Der heilige Georg, the material on Pope Sylvester I from Kondrad von Würzburg's Legenden, and the Barlaam und Josaphat by Rudolf von Ems. In addition to thirteenth-century sources, Prautzsch analyzes selections from the Vulgate Bible as well as relevant texts from the early Christian period that provide models and prototypes for narrating encounters between saints and unbelievers in the Christian tradition.

Prautzsch organizes this material into a consideration of three types of holy person: the martyr (chapter three), the soldier-saint (chapter four), and the missionary (chapter five). He notes that these may seem to align with three forms of religious expression that Jan Assmann and others have ascribed specifically to Christianity and monotheism: dying for God, killing for God, and converting unbelievers to God. However, Prautzsch argues that contrary to what much modern scholarship and the context of the Crusades might suggest, hagiographic narratives of encounter between their holy heroes and non-Christians never associated killing in the service of God with sanctity. Soldiers (including those eventually recognized as saints) could fight justly in support of a divinely ordained worldly authority, or in defense of Christianity and the Christian holy places, but none of these activities had the potential to display saintliness. The military activity of soldier saints like Sebastian and George on behalf of the pagan Roman Empire is not called into question as unjust or contrary to their status Christians, unlike sacrifice to the imperial cult. However, that activity is narratively isolated from, as temporally prior to, the exceptional valor in proclaiming their faith, converting unbelievers to Christianity, and willingness to die in pursuit of those endeavors that mark the soldier-saint as holy through encounter with and in contrast to the unbeliever. Although the papacy instituted Crusade indulgences and supported the concept of military activity in God's service as penitential, no one was proclaimed a saint simply by virtue of their participation in a crusade, as Prautzsch pointedly observes. Even Louis IX of France, much to Jean de Joinville's chagrin, was canonized as a confessor to the faith rather than as a martyr who died fighting against the Muslims of Tunis.

Prautzsch makes a strong case that, whatever may be found in other materials, the narrative sources produced in the thirteenth century to define the lives and virtues of exemplary saints could encompass warfare as just, even holy, as in a biography of St. George written for a courtly audience by the poet Rudolf von Ems, but not as a way to demonstrate sanctity through killing on the battlefield. Instead, these narratives always showed the saint as committed to disseminating the faith through some combination of spreading Christianity through the spoken word and demonstrating an exemplary willingness to commit one's whole being to witness the truth of the faith through the embrace of martyrdom, whether or not that embrace of martyrdom resulted in actual death at the hands of an unbeliever. The formal opposition between saint and heathendom in such legendary encounters functioned to achieve Identitätsbildung for thirteenth-century audiences. By systematically contrasting the categories of saint and heathen, these narratives constructed and communicated a normative identity for ordinary Christians: one in which the embrace of religious truth (shared with saint) combined with the heathen-like status of potentially but not yet actually having achieved salvation. The saint's encounter with Heidentum also had to communicate the miraculous actuality but also rarity with which transcendent reality was made immanent through the exemplary actions and achievements of missionary and martyr.

In addition to analyzing thirteenth-century representations of early Christian saints, Prautzsch also covers the encounter between St. Francis of Assisi and the Mamluk Sultan al-Kamil as described by Thomas of Celano, Bonaventure, and Lamprecht von Regensburg. He does so in his chapter on martyrdom, as these vitae communicate the saint's powerful desire to die for God as witness to the faith, later achieved symbolically through receipt of the stigmata. Giotto's fresco from Assisi depicting this encounter provides the cover image for the book. However, Prautzsch's handing of the Francis material is not fully persuasive. He notes, but does not explore, why the mission to Egypt is described in only some of the thirteenth-century vitae of Francis. He also does not adequately contextualize this specific encounter within the narrative totality of those texts that do include the incident. Finally, Francis is the only thirteenth-century saint whose hagiographic representation is discussed at any length. Within these limits, Prautzsch's analysis does suggest that representations of contemporaneous thirteenth-century saints shared a form and function with representations of early Christian saints. This is a topic well worth further research. Prautzsch's book demonstrates that legenda provided a key mechanism for defining and articulating engagement with the non-Christian other in the crusading context, despite or even because of this genre's overall rejection of crusade as an organizing theme.