In 2017 I presented the kernel of this book in a paper delivered at the International Congress on Medieval Studies to a room full of people interested in Franciscan theology. Based on the comments and questions that followed, it became immediately clear to me that even those of a generally Franciscan inclination were not only unacquainted with one of the greatest theologians of their tradition but also acutely misinformed about him. Many have wished to identify John Duns Scotus as the origin of some great modern ill, but even those who have engaged his thought more positively have generally been interested primarily in his philosophical ideas. Even those interested in his theology have focused the lion’s share of their attention on issues related to what we would now categorize as philosophical theology. All of this positive attention is, of course, licit and welcome, but I wish to present him here as theologian proper, one of the great theologians of the tradition who have expended all their considerable intellectual capacities in the service of reflecting on the core mysteries of the Christian faith. Writing on Scotus’s understanding of the relationship between grace and the Trinitarian missions—the Incarnation of the Son and the indwelling of the Holy Spirit—has allowed me to introduce a great number of Scotus’s theological insights that are of interest to me and, I expect, to many others.
Given my intention to introduce Scotus as theologian to theologians, both historical and systematic, I have made a number of strategic decisions that may not please all. First, while this book will often trace very particular technical questions through the late thirteenth and early fourteenth centuries in order to shed light on the significance of Scotus’s positions, this book is not really about Scotus’s immediate context. In it I argue that Scotus has been wrongly inscribed in the dominant narrative of the development of the medieval theology of grace, and because the dominant narrative runs from Aquinas through Scotus to Ockham, Aquinas and Ockham will feature prominently in this book even though Aquinas was not a primary thirteenth-century interlocutor for Scotus and there were many alternatives to Ockham in the fourteenth century. In addition, because I hope to introduce Scotus even to those not well trained in medieval theology, the decision to situate him in relation to Aquinas and Ockham is warranted by the fact that they are the two best known medieval theologians to the broader theological world.
Second, I hope that this book will stimulate interest in Scotus not only as historical figure but also as contemporary resource. To that aim, I will sometime extend somewhat beyond what Scotus himself has said to make