Defending the Church’s Language for the Trinity, with Gregory of Nyssa

There have been recent attempts, in some circles, to shift our language about the Trinity away from the biblical and traditional words Father and Son. Often rooted in concerns about gendered language, some liturgists offer gender-inclusive alternatives that replace not only the words but the father-son relational dynamic in our language about God. This phenomenon is not exactly new.

While it may be obvious that these perhaps well-intentioned attempts at gender-inclusive language unmoor Christian practice and thought from Scripture and centuries of Christian theology and potentially alter our received understanding of God, they also bear a striking resemblance to physiologein, an ancient heresy taught by the Arian theologian Eunomius (d. 393). Thus such attempts, however well-intentioned, can be similarly critiqued using the theological insights of Gregory of Nyssa (c. 335-c. 394).

The Error of Physiologein

Eunomius, a leading proponent of Arianism in the fourth century, held that God’s essence could be fully known by human reason. His theology reduced God to a singular, easily definable attribute: being unbegotten. From this precept, Eunomius argued that the Father’s unbegotten nature made him superior to the Son, who was begotten, and the Holy Spirit, who proceeds. This rational approach to God’s nature is what Gregory of Nyssa condemned as physiologein, or the attempt to rationalize and define the divine essence in human terms.

Eunomius relied heavily on human reasoning, attempting to explain the relationship within the Trinity through philosophical deduction. His insistence on the Father’s superiority over the Son was rooted in his belief that being unbegotten was a defining feature of the divine essence, something that could be fully comprehended by human intellect. In this way, his physiologein reduced the mystery of God to a simple formula, one that denied the equal divinity of the Son and the Holy Spirit.

Gregory of Nyssa, in Against Eunomius, thoroughly refuted this approach. He argued that God’s essence is utterly incomprehensible, and that human reason is insufficient to grasp the full reality of the divine. Gregory wrote, “For even to think that God can be apprehended by human reason is to offend against the majesty of God,” highlighting the arrogance inherent in Eunomius’s claims. For Gregory, any attempt to fully define God through human categories diminishes the divine mystery and leads to theological error.[1]

Contemporary Theology and Physiologein

The recent trend among some writers and liturgists of replacing Father and Son in theological discourse mirrors Eunomius’s error in significant ways. Just as Eunomius sought to rationalize and reduce God’s nature to a knowable essence, this new theology attempts to redefine God according to contemporary concerns about gender inclusivity. In doing so, it risks losing the profound theological depth and mystery that the traditional language conveys.

Father and Son are not merely human constructs; they are deeply rooted in the Christian understanding of the Trinity as revealed in Scripture and affirmed by centuries of theological reflection. Jesus repeatedly refers to God as Father dozens of times in the Gospels, so many that even listing examples in this space would seem pedantic. Even so, the relationship between the Father and the Son is central to the doctrine of the Trinity. To replace these words with more neutral language is to ignore the relational dynamics inherent in the Godhead and the revealed nature of God in Christ.

Gregory of Nyssa’s critique of Eunomius is highly relevant. Just as Eunomius sought to replace the revealed mystery of the Trinity with a humanly comprehensible explanation, some contemporary theologians who wish to redefine God’s relational language are imposing present-day concerns onto the divine nature. This is an inverted way of understanding biblical language and concepts. That God the Father is a father should tell us something about what it means to be a Father rather than an opportunity for us to impute or reject our imperfect experiences of fatherhood onto God.

In other words, God the Father shows us what it means to be a father, not that God becomes the white board onto which we project our less than ideal and sometimes problematic experiences of fathers (Luke 11:13). In short, there is a tendency to reduce the mystery of God to something more easily grasped or accepted by human culture, rather than accepting that God, who is beyond full human comprehension, has chosen to reveal himself in this way, as Father.

Gregory writes, “The Divine Nature surpasses every intellectual perception and every form of comprehension.”[2] This applies equally to Eunomius’s attempt to define God’s essence as unbegotten and to modern attempts to redefine God in terms that conform to contemporary social concerns. Both approaches risk diminishing the transcendence and mystery of God, as well as his immanence and self-revelation.

The Trinity’s Relational Nature

Father and Son in Christian theology are not merely metaphorical; they describe the real relationship within the Godhead. The Father begets the Son, and the Son is begotten by the Father, but this does not imply any form of inequality or subordination. Rather, these words reflect the relational nature of the Trinity, in which each person of the Godhead shares the same divine essence while existing in distinct relational roles.

Gregory of Nyssa was adamant in defending the co-equality of the Father, Son, and Holy Spirit against Eunomius’s subordinationist views. Eunomius’s insistence on the Father’s superiority over the Son was based on his failure to understand the relational, rather than hierarchical, nature of the Trinity. Gregory sees the life of the Holy Trinity as a mystery of perfect , with unbegottenness and begottenness not implying any inequality of essence or dignity within the Godhead.[3]

This insight is crucial when considering modern attempts to redefine the language of the Trinity. Father and Son convey not just the relational roles within the Trinity but also the unity and equality of the divine persons. To replace these words with other language risks obscuring this essential aspect of Trinitarian theology. Gregory’s critique of Eunomius can be applied here: just as the physiologein misrepresented the relationship between the Father and the Son by reducing it to a hierarchy, so too do contemporary attempts at revision misunderstand the relational dynamic within the Trinity.

The Danger of Rationalizing the Divine

Gregory’s critique of physiologein extends beyond the specific theological errors of Eunomius; it serves as a warning against any attempt to reduce the mystery of God or to deny, however subtly, that our language of God emerges not from our creative, even poetic, imaginings about God but from his self-revelation. In Gregory’s view, theology and prayer are not about mastering knowledge of God but about entering into a relationship with the divine mystery, the God who has chosen to make himself known to us in particular ways.

Gregory’s theology emphasizes that the mystery of God’s nature should evoke awe and humility in light of God’s majesty and his self-revelation. Father and Son are not arbitrary or culturally contingent; they reflect the eternal and unchanging reality of God’s relational nature as revealed in Scripture. To abandon these words in favor of other words is to miss the deeper theological truths they convey and the source of these words: God himself in Scripture.

Conclusion

The movement to replace the traditional language of Father and Son in Christian theology with other words reflects a tendency similar to the physiologein of Eunomius: both seek to rationalize and redefine the nature of God according to human understanding. Gregory of Nyssa’s critique of Eunomius offers a powerful rebuttal to such efforts. He reminds us that God’s essence is beyond human comprehension and that attempts to fully explain or redefine God beyond his self-revelation ultimately diminish the divine mystery.

Thus, in light of Gregory’s theology, any attempt to introduce inclusive language in the liturgy should be seen as an inappropriate adaptation of divine revelation to contemporary social concerns, ultimately leading believers away from the mystery of God. The vocation of the church is to share what we have received, that is, an abiding and healing knowledge of this loving Father who has reconciled with us through his Son and who in the power of the Spirit has adopted us as his own. And in this gospel, we have peace.

As Gregory says “Knowing, then, how widely the Divine nature differs from our own, let us quietly remain within our proper limits. For it is both safer and more reverent to believe the majesty of God to be greater than we can understand, than, after circumscribing His glory by our misconceptions, to suppose there is nothing beyond our conception of it.”[4]

1. Gregory of Nyssa. Against Eunomius, Book 1.
2. Ibid.
3. Gregory of Nyssa. On the Holy Spirit.
4. Gregory of Nyssa. Answer to Eunomius’ Second Book.