With this compelling volume, Oliver O'Donovan brings to a completion his remarkable trilogy ‘Theology as Ethics’. The entire trilogy can be understood as a kind of phenomenology of Christian formation, which perforce includes within it a phenomenology of the moral life more generally. Indeed, the heart of this third volume is a careful consideration of the relationship between the moral life in general and the Christian moral life shaped by the twin revelation of the divine creation of all things and the eschatological future when Christ will be all in all. Taking the entire trilogy into view, the first volume, Self, World, and Time, focused on the study of ethics itself and accordingly introduced some of the key theories and terms through which we might think about human moral action. In the second volume, Finding and Seeking, O'Donovan turned his attention from thinking about the way we think about moral action to a consideration of moral deliberation, decision and action itself. In this final volume, O'Donovan turns from the process of moral deliberation to treat instead the ends and objects of such deliberation, ‘the forward horizon with which moral thinking engages’ (p. vii).

Throughout his trilogy, O'Donovan demonstrates how moral philosophy, theology and a deep scriptural imagination can be integrated to powerful effect. He begins this volume, for example, by meditating upon St Paul's First Letter to the Corinthians, in particular Paul's surprising reordering of the theological virtues: faith, love and hope. Why, at the conclusion of chapter 13, does Paul draw such attention to his inversion of this triad? What is at stake in Paul's claim, ‘And now faith, hope, and love abide, these three; and the greatest of these is love’? O'Donovan argues that the Pauline supremacy of love moves us beyond the kind of moral apophaticism and infinite metaethical deferral that a messianic ethics of hope perforce entails. Instead, we are directed to a vision of love as ‘devotion’ and to the finality of community, a finality that can only be achieved on the other side of time (i.e. on further side of hope) but that is given to us in a revelation of the ultimate intelligibility of purposive moral reason.

In this sort of an argument we see O'Donovan's well-known Augustinianism on display: the goods of the moral life without which we cannot live, without which we would hardly be the kind of creatures we are, nevertheless only find their fulfilment, ultimate intelligibility and final flourishing in the eschatological renewal of God. As O'Donovan writes, ‘The entering of the end of history into temporal existence is how a coherent moral reason is made possible’ (p. 158). At the centre of this renewal lies the community constituted by love: in the enjoyment of this community with one another and God our moral action comes to rest. In one of the richest chapters of the work, O'Donovan considers the constitution of this community through the concept of communication, a term he reads as the operationalisation of the New Testament notion of koinonia. The logic of communication, evident especially in the eucharist, is participation, sharing, communion: what is mine is only mine because it is more ultimately ours (p. 48). Because human beings are created as social creatures, the rest to which we are finally called necessarily involves such communication (p. 135).

Through a series of pastorally rich and intellectually dense chapters, O'Donovan demonstrates the way that practical moral reason only enters into its rest and so only finds its fulfilment in God's recreation of the world through Christ. O'Donovan deftly explores the implications of this through a series of chapters dealing with such concepts as work, meaning, friendship and sanctification.

Although there is a tremendous amount to be said for the Augustinian vision animating the entire trilogy, and a cascade of fascinating arguments to be had along the way, perhaps the most notable achievement of this volume (as with its predecessors) is the extraordinary sagacity and immediacy of O'Donovan's voice. At the end of his long career, O'Donovan writes as one who has, as it were, come to rest in the vision and vocation to which he himself was given. The attempt to fit so richly meditated a vision into a single, deceptively thin volume confers on the writing an almost gnomic quality; almost every sentence appears both as an ordinary member of a perfectly decent paragraph, on the one hand, and explodes with aphoristic density, on the other. Reading O'Donovan is accordingly an uncommonly invigorating experience, but this is not to say he is self-evidently right in all of his judgements nor in his mode of expression. He has much less of an ear for the theologies and hermeneutics of the high Middle Ages, for instance, than he does for either for either antiquity or the post-Reformation period, and there are occasional infelicities with regard to gender that may cause some readers to grimace (e.g. his entirely unnecessary reference to ‘office girls … laughing over their selfies’, p. 147). It would, however, be a mistake to allow such concerns to detract from the evident achievement of both this volume and the entire trilogy, which deserves a place as one of the truly great theological works of recent decades.