Dietrich Bonhoeffer and Hans Frei are two of the twentieth century's more enigmatic Christian theologians, having been championed, or more frequently, maligned by liberals and conservatives alike. Yet there has been little comparative work done on the two. Stepping into the breach, Tim Boniface's recent book shows that reading Frei and Bonhoeffer together is both mutually clarifying and provides the constructive means of bolstering certain aspects of their respective theologies that remain underdeveloped. The result is a compelling account of divine transcendence that is not opposed to, but is rather premised upon, an affirmation of Jesus’ historical specificity, yielding a vision of theology that is confident in its affirmation of the uniqueness of Jesus Christ yet suffused with a generous humility. ‘Awareness of the unsubstitutable paradox of the transcendent Christ’, Boniface writes, ‘strengthens the quest for a way between closed and wide-open religion’ (p. 222).

Though the book is devoted to the work of Frei and Bonhoeffer, the first chapter is a summary of William Placher's The Domestication of Transcendence, narrating how, ‘from the seventeenth century onward’, the ‘notion of God's otherness was effectively reversed by being reduced to something human beings can grasp about God – i.e. God's ‘transcendence’ – on the basis of universal reason’ (p. 2). This obscures the particularity of God's self-revelation in Jesus of Nazareth and, in turn, advances a view of God's transcendence that masquerades as humble but in effect is the height of hubris. Placher, once Frei's student at Yale, provides clear and succinct support for Boniface's conviction that ‘the question of the transcendence of Jesus, thought through especially in response to post-Enlightenment epistemology’, remains a crucial concern for contemporary theology and ‘lies at the heart of what makes both Frei and Bonhoeffer promising for the pursuit of [a theological] “middle way” … an account of the paradoxical transcendence of Jesus, at the heart of which is his scandalous historical particularity’ (p. xiv).

Following this, Boniface takes on the theologians in turn, devoting the two subsequent chapters to Frei, and the three following those to Bonhoeffer. These chapters reveal not only how much the two have in common but also how mutually enriching their theology is. Indeed, while both begin with a basic concern about ‘the impact of the epistemological constraints placed upon theology by modernity’ and a shared ‘determination to maintain the integrity of the historical in relation to God's transcendent activity’ (p. 211), they pursued these concerns and convictions through rather different paths.

And it is just for this reason that pairing the two is so worthwhile. Both maintained that ‘Christology is about the “who” of Christ’ (p. 213), an exercise of faith seeking understanding that is at once confident and humble, eschewing apologetic approaches to christology that prioritise domesticating questions like ‘how?’ But Frei made this case largely by focusing on hermeneutics and historicity while Bonhoeffer attended to christology and ecclesiology. Exploring ‘Frei's concepts of unsubsitutability and his explication of the praxis of figural reading, and Bonhoeffer's theologia crucis and his participatory ontology’, Boniface demonstrates how these two theologians ‘add significant depth to the other's work, toward a stronger account of a theology of the transcendence of Jesus that in turns grounds a simultaneous confidence and humility’ (p. 222).

While Boniface's synthesis of Frei and Bonhoeffer is on the whole very convincing, there are, inevitably, points at which it can feel slightly strained. A lengthy section on Christ's ‘incognito’ somewhat obscures Frei's surprising emphasis on this with regards to the encountering of Jesus beyond the confines of Christian scripture, tradition and community. Boniface instead depicts Frei's invoking of Jesus’ incognito as akin to Bonhoeffer's focus on the hiddenness of a God revealed on the cross. One can also imagine Frei in particular fretting about the book's pursuit of humility as a theological virtue, which at times Boniface appears to treat as an end in itself and even as a systematic feature of Christian theology. But at other points he makes clear that the kind of theological humility he is after, and which emerges from the work of Frei and Bonhoeffer, is most closely associated with ‘a posture of worship’ (p. 106). Such humility is therefore a function of the community's confidence in the centrality of the unsubstitutable person of Jesus, who yet also imbues such confident commitment with ‘a sense of the impossibility of grasping and containing this transcendent person’ (p. 234). Boniface has here made an important contribution not only to the respective scholarship of both Frei and Bonhoeffer, but also to the ongoing debate about the nature of Christian theology itself.