Note: From Nationalism and Heresy in Augustine (Wipf & Stock, 2026). Reprinted by permission of the publisher. Citations have been omitted.
I have become the living embodiment of the old joke about the philosopher who climbed the mountain and found the theologians up there waiting for him. This book is the unexpected result of a five-year interdisciplinary research project. After twenty years of work in political philosophy, I concluded that only theology could fully answer the questions I was asking. So I started over, hoping that insights from my first research career could be useful in launching a second one.
I set out to search Augustine’s theology of public life for retrievable resources to help Christians respond to religious nationalism without overreacting into religious isolationism. I knew that fourth- and fifth-century Rome, while very different from our own time and place, was at least analogous in that both periods involve the challenge of religious pluralism. Rome in Augustine’s day hoped to have a common good without a common god – social solidarity without a fully shared sense of the sacred. My own hope was that a fresh encounter with Augustine’s revolutionary response to this challenge might provide us with theological resources for something other than the visceral “fight or flight” alternatives of religious nationalism and religious isolationism.
I knew that, like the proverbial scorpions in a bottle, religious isolationism inflames religious nationalism, and religious nationalism inflames religious isolationism. In Augustine’s time as in our times – we will see in the coming pages – those who invested ultimate religious significance in Christian political success were strongly reinforced in their views by their horror and disgust at those who insisted that Christian faithfulness required complete separation from public affairs, and vice versa. And I knew that Augustine had articulated a theological method for uncorking that bottle.
I was not prepared, however, for how much further than that Augustine was prepared to go. He presented a serious and sustained theological argument that if the scorpions of nationalism and isolationism refuse the invitation to come out of the bottle and surrender their stings, the church has a responsibility to protect the purity of the gospel by casting the bottle into the sea. The more I scrutinized Augustine’s case, the more persuaded I became that this aspect of his theological approach to public life could provide the ballast so desperately needed in a church blown about by winds of nationalistic and isolationist doctrine.
Thus I return from my Augustinian pilgrimage making a claim that I never could have expected when I set out five years ago: Augustine’s theology of public life suggests that Christian doctrinal orthodoxy is at stake in the church’s struggle against religious nationalism and its alter ego, religious isolationism. Orthodoxy requires both that we distinguish and that we not separate the social categories that are today called the “political” and the “religious” – exactly as orthodoxy requires both that we distinguish and that we not separate the three persons in God, or the two natures of Christ, or faith and works. To put it in anachronistic but accurate terms, Augustine suggests that the failure of both religious nationalists and religious isolationists to maintain this distinction-without-separation between politics and religion reflects a Pelagian soteriology that trusts in human moral agency for a salvific power that Christian orthodoxy forbids us to find anywhere but in God alone.
For some time, the mainstream scholarly interpretation has been that Augustine treats the public life of society as a tertium quid – a “third thing” – standing in between the good spiritual life of believers and the evil spiritual life of unbelievers. For Augustine, public institutions and identities are a shared and ambiguous point of encounter between the church and the world. A central argument of this book is that Augustine’s treatment of public life as a tertium quid emerged from his concern to protect soteriological orthodoxy. To collapse all human social experience into two spiritually homogenous spheres without recognizing a shared and ambiguous point of encounter between them is both the result and the cause of a Pelagian trust in human moral agency for salvation.
Augustine makes an explicit and formidable case that those who absolutely separate what we now call the political and the religious are damnable heretics, and an implicit but equally formidable case that those who absolutely refuse to distinguish them are damnable heretics. The former case is the one he made against the Donatists, and once we set aside ossified historical misunderstandings in order to re-familiarize ourselves with the profound theological implications of the Donatist controversy, it is not difficult to see how extreme forms of religious isolationism in any historical era can come into conflict with orthodox Christian soteriology in exactly the ways Augustine explicitly identified. The latter case is the one he made in De Civitate Dei against those who followed Christian thinkers like Eusebius in identifying the success of Christianity with the success of Roman political power, and once we recognize the extent to which the argument of De Civitate Dei that it is “pagans” who worship political power and that “Christians” could never do such a thing is aimed at least as much at correcting Eusebian Christians as it is at converting pagans, it is not difficult to see how extreme forms of religious nationalism in any historical era can come into conflict with orthodox Christian soteriology in exactly the ways Augustine implicitly suggested. In both cases, Augustine diagnoses the cause of the heterodoxy as trust in the human will for salvation, and the logic of his arguments in these earlier debates laid the foundation for the case he would later go on to make against Pelagianism….
Dropping the H-Bomb
If this book is right that Augustine offers a substantial theological argument that certain approaches to public life, at least in their extreme forms, are heretical, it seems likely to follow – shocking as this may be – that the historic contribution of Augustine’s theology of public life has actually been underestimated….However, developing a case for this proposition is outside the scope of the present book; the job of this book is to provoke that question, not to answer it.
Readers will not have been slow to realize another implication that seems likely to follow if this book’s claims about Augustine are correct. We would be confronted with the urgent question of whether Augustine may, in fact, have been correct in his view that there are doctrinal boundaries limiting what approaches to public life are consistent with Christian orthodoxy. And this must lead us to consider what the ecclesial status of these boundaries ought to be today. Should it be possible for an individual to be excommunicated, or a church body to lose ecclesial recognition by other church bodies, on grounds of religious nationalism or isolationism in forms extreme enough to be inconsistent with Christian doctrine?…
The limits of what this book is claiming, as distinct from the subsequent questions that would be raised if its claims are correct, will hopefully become clearer when the central claims of this book are restated in the following highly formal manner: 1) Augustine’s arguments against the Eusebian views that dominated European Christianity and the Donatist views that dominated African Christianity in his time centered on claims that their approaches to social categories were inconsistent with Christian soteriology, for reasons closely paralleling those he would later give in his arguments that Pelagianism was a damnable heresy; 2) Augustine thought it was an important point that the soteriological deficiency in Donatism was not just an error but a damnable heresy, and his argument on this point merits close scholarly attention, so the tendency of recent theological scholarship to treat his case dismissively and even derisively ought to be corrected; 3) Eusebianism was not an organized school of thought, so Augustine did not address it as if it were, but his soteriological case against Eusebianism in De Civitate Dei constitutes an implicit and important argument that Eusebianism is not just ethically bad but actually outside the doctrinal bounds of orthodox Christian identity; 4) the approaches to social categories in Eusebianism and Donatism that Augustine found soteriologically inconsistent with Christian identity are recognizable as constituent elements of religious nationalism and isolationism as general human phenomena, so his arguments that Eusebianism and Donatism were doctrinally outside the bounds of Christian identity in his own time and place are, at minimum, relevant to consideration of religious nationalism and isolationism in other times, including ours.
The careful reader will note, then, that this book is not calling anyone a heretic. It is not even calling for anyone to be called a heretic. It is calling attention to the fact that Augustine explicitly called millions of people heretics, and implicitly millions more, because of their soteriologically deficient approaches to social categories. And by inviting a comparison between Augustine’s theology of public life and our own theologies of public life (or lack thereof) it is calling for a recognition of, and a reconsideration of, the current state of affairs in which there are no ecclesially enforced boundaries controlling what Christians can say about public life consistent with orthodoxy. Such a recognition and reconsideration might not result in anyone’s being called a heretic. But it would result in many people’s being called to develop a more robust theological understanding of public life. And it would call theological scholars to examine much more carefully the set of social categories that first emerged in the seventeenth and eighteenth centuries and that has, in the brief time since then, come to dominate our social imaginary almost totally. Just what is a “society” or a “culture,” anyway? We talk about them all the time, but we have yet to develop a compelling theological account of what these newly minted social categories are, and how they relate to Christianity’s gospel message.
Heresy has never at any time meant simply “wrong opinion.” Closely following Paul’s theological deployment of the Greek hairesis, “to make a choice,” the church developed the concept of heresy more or less without further alteration of that word’s core meaning. Heresy means going your own doctrinal way – making your own choices as if theology were a vast all-you-can-eat buffet, rather than receiving submissively the strict nutritional regimen prescribed for our dietary needs by divine revelation. It is especially difficult, and especially important, for people living in modern culture – where personal choice has become all-pervasive and is jealously cherished – to recover a robust appreciation of this original meaning of this term. That the essential core of heresy is located not in the mind but in the willfulness of the heretic serves as a reminder, on the one hand, that we are not called to galivant about the land excommunicating people for mere intellectual error, and on the other hand, that the integrity of the faith does require the church to exercise discipline over willful persons who place themselves within the congregation of the faithful – or the pulpit! – and then arrogate to themselves the right to invent new religions and call them “Christianity.”
Christianity cannot, speaking in a human way, remain theologically authentic and legitimate without the unpleasant duty of boundary-policing. This is above all true in an age of radical individual choice. In today’s world, whatever a given church does not clearly and unambiguously exclude will be part of its organizational life, and hence its spiritual life.
Boundary-policing is a dangerous job, above all spiritually dangerous; it can itself be a primary locus of nationalist or isolationist passions. However, logically there is no escaping the necessity of the task if we care about what Christianity is and how the church embodies it. It takes nothing away from God’s providential superintendence of all events to recall that the job of declaring what is and what is not acceptable within the ambit of Christian doctrine has been explicitly delegated to church officers by the Lord of the universe. Augustine, like many other theological figures, offers retrievable resources that could provide a plausibility structure for declaring that extreme forms of religious nationalism and isolationism are not merely unjust and imprudent, but theologically anathema – inconsistent with our gospel.
Greg Forster, affiliate professor of biblical and systematic theology, Trinity Evangelical Divinity School; and president, Karam Fellowship
