The Covenant Universalist: Gregory of Nyssa’s Refutation of Manichaeism and the Problem of Eternal Evil in Orthodox Christianity

by Rev. William M. Brennan, TH.D.

Introduction

The struggle between early Christianity and Manichaeism was not merely a contest between rival religions but a profound metaphysical dispute concerning the nature of evil, matter, and the ultimate destiny of creation. Gregory of Nyssa, one of the Cappadocian Fathers and a central architect of Nicene orthodoxy, stands as one of the most philosophically rigorous opponents of Manichaean dualism. While Gregory unequivocally rejects Manichaeism’s doctrine of two eternal principles, his eschatological vision—particularly his insistence on the final abolition of evil—raises a critical question: did later orthodox Christianity, by affirming the eternal existence of hell and the everlasting exclusion of some creatures, unintentionally reintroduce a Manichaean structure at the level of outcome, if not at the level of origin?

Gregory of Nyssa (c. 335–395 CE) stands among the most authoritative theologians of the fourth century and occupies a central place within the pro-Nicene settlement of early Christianity. As one of the three Cappadocian Fathers—alongside Basil of Caesarea and Gregory of Nazianzus—he was instrumental in articulating and defending the theological grammar that secured the triumph of Nicene orthodoxy against Arianism, particularly in its doctrines of divine unity, Trinitarian relations, and the goodness of creation. His theological standing has never been seriously contested within the orthodox tradition; indeed, he is frequently honored in the Eastern Church as “the Father of Fathers,” a title reflecting both his doctrinal authority and his enduring influence on patristic theology. Notably, this unimpeachable orthodoxy coexists with Gregory’s explicit commitment to a universalist eschatology (apokatastasis), a position he defends not as speculative novelty but as the necessary consequence of Nicene metaphysics consistently applied. That Gregory could be simultaneously an ardent universalist and a chief architect of orthodoxy poses a significant challenge to later theological claims that universal restoration is inherently heterodox or implicitly Manichaean.

The choice of Gregory of Nyssa as the primary interlocutor for evaluating the relationship between Christianity and Manichaeism is especially significant when contrasted with the later dominance of Augustine of Hippo, whose eschatological vision would come to exercise far greater influence over Western theology. Augustine’s authority gradually eclipsed that of Gregory, particularly with respect to the doctrine of final punishment and the permanence of exclusion, marking a decisive departure from Gregory’s universalist horizon. This divergence is historically noteworthy given Augustine’s own intellectual biography.

Prior to his conversion to Christianity, Augustine spent nearly a decade as a committed adherent and teacher within the Manichaean community founded by Mani. While Augustine explicitly repudiated Manichaean metaphysics after his conversion, it is neither implausible nor historically irresponsible to suggest that elements of Manichaean eschatological structure—especially the notion of an eternal remainder irrevocably excluded from the good—continued to shape his imagination. The enduring influence of Augustine’s theology thus raises the possibility that, in rejecting Gregory’s vision of universal restoration, later orthodoxy inadvertently preserved in modified form a Manichaean pattern of finality, even while denying its metaphysical premises.

This essay argues that Gregory’s refutation of Manichaeism is not limited to its cosmological beginnings but extends decisively to its eschatological conclusions. In failing to heed this aspect of Gregory’s teaching, later orthodoxy posited an eternal persistence of evil that risks granting it a quasi-substantial and functionally ultimate status—precisely what Gregory labored to deny.

I. Manichaeism as Metaphysical Target

Mani (c. 216–276 CE) taught a radical metaphysical dualism in which Light and Darkness are co-eternal, uncreated principles locked in cosmic opposition. Evil, identified with matter and chaos, is not a privation or distortion of the good but a positive, ontological reality. Salvation, accordingly, consists in the extraction of divine Light from material entanglement and its return to the realm of Light, while Darkness remains eternally sealed and contained.¹

Gregory wrote in a late-fourth-century context in which Manichaeism was a well-known and actively opposed rival system. His polemic, however, is directed less at Mani as a historical figure than at the metaphysical coherence of dualism itself.

II. Gregory’s Ontology: Evil as Privation, Not Substance

Across his corpus, Gregory insists on a single, foundational metaphysical axiom: being is identical with the good, because all being derives from God, who alone truly is. Evil, therefore, cannot possess positive ontological status.

In On the Soul and the Resurrection, Gregory argues that evil is not a thing but a lack:

“That which is evil is not contemplated as existing in its own substance, but is a certain absence and privation of the good.”²

This claim functions as a direct refutation of Manichaean ontology. If evil had substance, it would necessarily derive from God (which is impossible) or exist independently of God (which would negate divine ultimacy). Either option collapses Christian monotheism.

III. The Eschatological Extension of Anti-Manichaean Logic

Crucially, Gregory does not confine this logic to the doctrine of creation; he extends it into eschatology. If evil is privation, it cannot be eternal, for eternity belongs only to what truly is. In The Great Catechism, Gregory states:

“For it is not reasonable to suppose that what had its beginning in time should be co-eternal with that which had no beginning.”³

Punishment, therefore, is medicinal and purgative, not retributive in an endless sense. Evil is permitted only insofar as it can be undone.

Gregory explicitly interprets First Epistle to the Corinthians 15:28—“that God may be all in all”—as a literal eschatological claim. Any eternal remainder of evil would contradict this vision, introducing a permanent duality into the final state of reality.

IV. Direct and Indirect Refutations of Manichaeism

A. Direct Critiques

Gregory explicitly rejects:

Two eternal principles
Matter as intrinsically evil
Evil as a substantive reality

These are unmistakably Manichaean positions, and Gregory treats them as live philosophical errors rather than distant heresies.⁴

B. Indirect (Structural) Critiques

More subtly, Gregory rejects any eschatology that stabilizes evil forever, even if it verbally denies dualism. His reasoning is clear: an eternally preserved evil, even as “privation,” functions metaphysically like a second principle.

As he notes in On the Soul and the Resurrection, what is wholly deprived of the good must eventually cease, since persistence itself is a mode of participation in being.⁵

V. The Departure of Later Orthodoxy

Later Latin and medieval orthodoxy—especially in the Augustinian tradition—retained Gregory’s ontology of evil as privation but abandoned his eschatological conclusions. By affirming the eternal existence of hell and the everlasting exclusion of some rational creatures, orthodoxy introduced:

An eternal dual outcome
A permanent “outside” to divine reconciliation
An everlasting state opposed to the good

While evil was still denied substantiality, it was granted eternal duration, which for Gregory would amount to a contradiction. Duration without end is not metaphysically neutral; it confers stability, persistence, and a functional ultimacy.

Thus, although orthodoxy avoids Manichaeism in its beginnings, it risks approximating it in its end.

VI. Gregory and the Charge of “Implicit Dualism”

Gregory’s position suggests a striking conclusion: an eternal hell is not merely pastorally severe but metaphysically incoherent. To posit an everlasting realm of exclusion is to grant evil an unending role within the divine economy, undermining the claim that God alone is ultimate.

In this sense, Gregory anticipates later covenant universalist arguments, not as speculative optimism but as a strict consequence of anti-Manichaean ontology consistently applied.

Conclusion

Gregory of Nyssa stands as one of Christianity’s most formidable opponents of Manichaeism precisely because he recognizes that the defeat of dualism requires more than a monotheistic account of origins. It requires an eschatology in which evil is not merely restrained or contained, but abolished.

By failing to follow Gregory’s logic to its eschatological conclusion, later orthodoxy preserved a final structure that mirrors Manichaeism in form, though not in metaphysical intent. Gregory’s enduring challenge to Christian theology is thus not whether evil is created, but whether it is allowed to last forever—and what that allowance ultimately implies.

Notes

Iain Gardner, Manichaean Texts from the Roman Empire (Cambridge, 2004).
Gregory of Nyssa, On the Soul and the Resurrection,
Gregory of Nyssa, The Great Catechism, ch. 26.
Jean Daniélou, From Glory to Glory: Texts from Gregory of Nyssa’s Mystical Writings (St. Vladimir’s Seminary Press, 1995).
Morwenna Ludlow, Gregory of Nyssa, Ancient and (Post)Modern (Oxford University Press, 2007).