Lactantius, Eusebius, and the Transformation of Christian Apologetics in the Constantinian Era

In my dissertation, Lactantius, Eusebius, and The Transformation of Christian Apologetics in the Constantinian Era, I examine how Lactantius and Eusebius take up and transform Christian apologetics. Christian apologetics is a mode of discourse characterized by explanation/defense of Christianity or elements thereof with reference to the ostensible critiques or questions of non-Christians. This mode of discourse was present amongst the earliest generations of Christians, but the prolific and influential early fourth century authors Lactantius, in his Divinarum institutionum libri VII, and Eusebius of Caesarea, in his Apodeixis, are the first to offer systematic reflection and analysis of it. Both authors wrote their texts during the twenty years of the reign of Constantine (306–37 CE), a time when Christianity received imperial endorsement and Christians rapidly gained power in the emperor’s court and Roman society more broadly. I argue that apologetics proved useful to Eusebius and Lactantius as they sought to imagine a new kind of Christian elite, who could not only respond to philosophical critiques of Christianity, but who could also increasingly occupy new positions of privilege and responsibility in a Christianizing empire. Lactantius and Eusebius thus transformed Christian apologetics from a mode of discourse primarily reacting to the ostensible attacks of outsiders into a pedagogical discourse designed to shape religious insiders.
To understand how and why Lactantius and Eusebius transformed Christian apologetics, I first situate my analysis within some insights that have emerged from recent scholarly debates and discussions about ancient apologetics. These discussions have called into question the cordoning of apologetics in a pre-Constantinian age or in an “age of the apologists” in which Christians were especially marginal or disadvantaged. Recent scholarly debates and discussions have also illuminated the lack of consistent terminology in antiquity for the practice modern scholars tend to call apologetics and have concomitantly rejected the notion that there was anything like a proper “genre” of Christian apologetic writing. This is an important insight for my analysis, since both authors develop unique vocabularies to describe their projects and the projects of their literary predecessors. Finally, they have developed analysis of apologetics that explores its inter-communal and formative functions. The pedagogical themes that I argue are so powerfully present in both authors texts dovetails with these analytical focuses.
I next consider Lactantius in his Divinarum institutionum libri VII, where he describes a need for defense of wisdom and truth against anti-Christian ideas, a defense that is urgently needed because of the threat of physical violence against Christians. Lactantius articulates a lineage of previous authors of apologetic works upon whose work he will build, but who were ultimately inadequate to the task. Lactantius mentions a few disparate methodological mistakes and insufficiencies of rhetorical acumen that caused this failure, but fundamentally sees his predecessors’ mistake as “defending” but not “teaching.” Lactantius claims to be rectifying this situation by writing “institutiones” (pedagogical texts that introduce a discipline) that will not only correct error but also instill the truth and form a new kind of educated Christian. Thus, in Lactantius’ text the defense/response of apologetics is united with “instruction” and transformed into a tool for forming new kinds of Christian intellectuals.
Eusebius, in his Apodeixis, makes no distinction between “defense” and “instruction,” but instead claims to be writing a “demonstration,” whose hallmark is showing the inherent intelligibility and exclusive truthfulness of Christianity over against non-Christian practices or doctrines, in a distinguished line of previous authors going back to the apostle Paul. He argues that these demonstrations rightly serve a pedagogical function: they form and equip Christian intellectuals to contend with non-Christian peers and provide guidance for Christian inferiors. Recent scholars have emphasized the way Eusebius is articulating a kind of Christian ethnos in this text. My exposition builds on the arguments of this scholarship by noting that within this ethnos we find Eusebius focusing on the formation of the elite class within it. Therefore, in Apodeixis we see a project to form elite Christian intellectuals and also some description of what role these elite will play amongst religious outsiders and co-religionists.
This dissertation shows how Christian apologetics was re-imagined in the early fourth century by Lactantius and Euesbius, who transform this mode of discourse within a broader pedagogical frame designed to form Christian intellectuals. The similarity in these authors’ projects suggest that they both see the apologetic mode of discourse as an important, perhaps essential tool in forming Christian intellectuals for the new situation of Christianity in the first three decades of the fourth century. Finally, by showing how Christian apologetics was similarly transformed by Lactantius and Eusebius, I demonstrate previously unseen similarities between the Divinarum institutionum libri VII and Apodeixis.