This scrupulously well-documented book is the fruit of a labour of love. Its author, Hans Boersma, is a Protestant. As such, he has written this erudite analysis of French Catholic ressourcement theology, otherwise known as the Nouvelle Théologie. The ‘New Theology’ was novel in its re-formulation of the task of theology amid neo-scholasticism's grip on Catholic theology that was firm notably from the late nineteenth century to the decades following the Second World War. Its nemesis was manualist theology. The nouvelle theologians, mostly French Dominicans and Jesuits, earned their appellation from their neo-scholastic interlocutors and detractors, who were generally disinclined to engage in intellectual dialogue with their decidedly modern contemporary cultures. By contrast, the nouvelle theologians aspired to impel such a dialogue by a method of ressourcement, that is, by going back to and re-engaging Catholic theology with the sources of what Boersma refers to as ‘the great Tradition’: the common western and eastern legacy articulated in the creeds and the writings of the church Fathers. The Saulchoir Dominicans, Chenu and Congar, were particularly keen to return to the medieval theologies as a rediscovered resource for theology, while Jesuits of Lyon-Fourvière, such as de Lubac, Daniélou and Bouillard, together with the Swiss, von Balthasar, were greatly stimulated by the Greek Fathers. The dominating thread of argument running though Boersma's tome is that the principal goal of ressourcement was to revitalise theology though a rediscovery of a sacramental ontology which suffuses ancient and medieval theologies, and which did not bifurcate nature and supernature in the way that nouvelle theologians charged that neo-scholastics did. Hence the subtitle of this book: A return to mystery. The nouvelle theologians wanted above all to breach the chasm between nature and supernature established by neo-scholastic theology by refocusing on an ancient attention to mysterium, or the reality of divine mystery. A sacramental ontology is one that views the created order, including the spirit of the human being, as representing sacramentally (as sacramentum) the supernatural reality (res) of the mystery of God.

Boersma weaves his analysis of nouvelle théologie through eight chapters focusing on the context and precursors of ressourcement, and then the different theologies of the principal nouvelle theologians themselves. This approach is limited as Boersma is keenly aware, because the collective output of the theologians concerned is too large to be presented comprehensively. Still, he unifies all of his discussions with attention to a rediscovery of an ancient sacramental ontology common to the theologians discussed. The book ends by teasing out the ecumenical implications of a reengagement with a sacramental ontology. The entire book is motivated by an ecumenical aim that was impelled by its author's initial reading of Congar. It presents a two-pronged challenge to Churches today. To Catholics, overly fixated on a doctrine of eucharistic real presence (since the Berengarian controversy), it invites them to recognise that sacraments signify and mediate the reality of a divine mystery which they do not possess in and of themselves. To Protestants, it calls on them to regain a lost appreciation of sacramental ontology that has spawned an overly rational theology and, like neo-scholasticism, widened a cleavage between the created order and its creator.