The concept of physicalist soteriology, as Ellen Scully defines it in this book, is a belief in humanity’s unity in Christ in which the incarnation is seen as enacting a ‘universal’ and ‘automatic’ change in human nature (pp. 5, 34–37, 293). It takes the incarnation to have an effect on all human beings and to have it ‘automatically’ – that is, without any need for an individual’s response to the gospel through faith, growth in virtue or participation in ecclesial sacraments. At the same time, this automatic and universal transformation is not necessarily salvific in an ultimate sense, and so does not negate the need for faith, virtue or the sacraments. This dynamic – whether it be labelled a tension, a paradox or something else – animates this timely and illuminating study of early Christian soteriology.

Physicalist soteriologies flourished in the fourth century, Scully argues, not because there was any concrete ‘tradition’ of physicalist soteriology but because a variety of thinkers organically came to similar views about the implications of the incarnation in tandem with concomitant beliefs about the doctrine of creation, ensoulment and transmission of sin alongside various emphases in fourth-century Christology – for example, a tendency to speak of the incarnation using various kinds of mixture Christologies before those were condemned at Chalcedon. In contemporary scholarship, however, the doctrine has largely suffered neglect due to von Harnack’s linking of the doctrine with universalism and the devaluation of human freedom.

Building on her previous research on this theme in the writings of Hilary of Poitiers, Scully explores the varieties of physicalist soteriology in six major patristic figures: Athanasius, Hilary of Poitiers, Marius Victorinus, Gregory of Nyssa, Cyril of Alexandria and Maximus the Confessor. A penultimate chapter surveys the ‘almost, but not quite’ physicalism of figures such as Irenaeus, Methodius, Philoxenus of Mabbug and John of Damascus, which helps to distinguish true physicalism from arguments that sound somewhat resonant with the doctrine but which, upon closer examination, do not intend quite the same thing. A final chapter outlines some of the constructive proposals for her thesis, both suggesting some ways that the doctrine might prove salutary for new ways of imagining human sociality but also addressing the Harnackian critiques. The methodology itself is a powerful rebuttal against the notion that there is any singular doctrine of physicalist soteriology that entails universalism or the diminution of personal agency in salvation.

Scully treats each of these six figures with chapter-length studies, highlighting each one’s unique emphases. Athanasius’ uniqueness is his consideration of the Holy Spirit as the primary agent of a reunified humanity, with the incarnation serving to transform human nature such that creatures become newly capable of receiving the Spirit and so the possibility of deification. Hilary’s is a ‘collective physicalism’ in which the incarnation renders all individual human beings as existing in Christ’s body, receiving an incorruptibility, though one that can be lost through individual choice. Marius Victorinus comes closest to Harnack’s view of physicalism, with the incarnation pictured as an assumption of a Platonic form of human nature. Victorinus’ proclivity towards universalism, however, is also allied with a strong emphasis on the need for individual faith. Scully’s chapter on Gregory of Nyssa affirms Gregory to be a physicalist, which is a contested topic in Gregory scholarship. She qualifies this, though, by highlighting Gregory’s accent on the delayed effects of the incarnation and the need for ecclesial participation. Appealing to Gregory’s mixture Christology – Christ’s human nature as a drop of vinegar engulfed in an ocean of divinity, or as the divine yeast gradually leavening the lump of humanity – Scully argues that while Gregory’s physicalism is theologically linked to universalism, human salvation is immediate but acquired progressively, and which places a heavy emphasis on the need for the sacraments. In the writings of Cyril of Alexandria, the incarnation’s main effect is to save every human from death, though this does not mean, Scully argues, that every human is ultimately saved: while all rise from the dead, not all rise to life with God. Finally, Maximus the Confessor’s view is tied to a creation ensoulment theory (God creates each individual soul and places it in a body received from one’s parents) and a clear-eyed focus on the Adam-Christ typology; for Maximus, the incarnation entails a universal effect on human bodies, but this still requires the Christian soul to become conformed to Christ through following the way of the cross.

Scully’s book is an exceptionally well-researched and well-conceived work of historical theology. It is carefully argued, precise in its definitions and judicious in its reading of sources. It is understated in its normative claims while still showing clearly the ways in which the doctrine of physicalist soteriology can be retrieved in contemporary theology. This was especially notable, as I have already suggested, in the book’s treatment of universalism. While writers such as Victorinus and Nyssen can be read as universalists, others such as Athanasius, Hilary and Cyril directly opposed the notion. Victorinus and Gregory, meanwhile, make clear that the logic of physicalism does not negate the need for faith or sacramental participation. Scully shows the variety of ways, in other words, in which these patristic theologians believed both that Christ’s incarnation has a transformative effect on all human nature automatically, while not thereby claiming that all human beings are automatically saved.

This last note poses a larger question, it seems to me, about how we locate the doctrine within the traditional range of theological loci. By tending this rift between physicalism and universalism – or rather, showing the compatibility of physicalism and the need for faith, virtue and the sacraments – it would seem to suggest shifting the doctrine away from the category of salvation and locating it instead more directly within the spheres of Christology or theological anthropology, or better yet, re-evaluating the utility of these categories for the study of early Christian theology. More interestingly, perhaps, Scully’s argument raises theological questions about the efficacy of the incarnation. If the incarnation transforms all human beings automatically, but it is not an automatic salvation for all, does this entail some sort of lack or deficit in the incarnation? What is it that changes in human nature? What then remains still in need of change? Or should this be narrated otherwise? These are questions I would be eager to hear elaborated further. What is clear, regardless, is that Scully has produced an exemplary work of historical theology, the implications of which stretch far beyond the book’s primary focus on physicalist salvation in early Christianity.