This project began in a conversation between the editors of the present volume at an Italian restaurant in Leuven, Belgium, in November 2005. At the time both of us had developed an interest in the topic of spiritual perception: Sarah Coakley was exploring the importance of the patristic teaching on the spiritual senses for systematic theology and philosophy of religion, whereas Paul Gavrilyuk had discovered how little the topic had recently been explored in patristic scholarship in general. In spring 2007, Coakley, who was then teaching at Harvard Divinity School, gathered a reading group of scholars from the Boston area interested in the topic at her house in Watertown, Massachusetts, for a series of informal meetings on Friday afternoons. Besides the two editors, the initial Spiritual Senses Group included Boyd Taylor Coolman, Garth Green, Paul Kolbet, Mark McInroy and Cameron Partridge. We looked at the theme of spiritual perception in the writings of Origen, Gregory of Nyssa, Pseudo-Macarius, Pseudo-Dionysius, Symeon the New Theologian, Thomas Gallus, Bonaventure, Immanuel Kant and Michel Henry. We also identified the central role that the work of Karl Rahner and Hans Urs von Balthasar had had in the rediscovery of the topic of the spiritual senses in twentieth-century theology. Towards the end of our spring meetings, we decided to produce a jointly written volume, with mutual understanding that most editorial responsibilities would be carried out by Gavrilyuk.

In order to discuss the individual chapters and to forge a coherent vision of the future volume, Gavrilyuk organized three consultations. The first consultation was hosted at Boston College in May 2008. At this meeting the original group was joined by Frederick Aquino and Richard Cross. The second consultation was held in Chicago in November 2008, and the third and final consultation took place in Montreal in November 2009. The original group kept growing, as William Abraham, George Demacopoulos, Gregory LaNave, Matthew Lootens, Bernard McGinn, Mark Mealey and William Wainwright joined in the endeavour. During each of the three consultations, about a third of all essays that would make up the volume were discussed. Thus the volume grew as a cooperative endeavour, as the authors read and commented on each other's work and contributed constructively to the Introduction. Derek Michaud and Garth Green offered important bibliographic suggestions. The editorial work on the volume was conducted with the help of Gavrilyuk's graduate students Stephani Atkins, Kyle Sellnow and Ry Siggelkow. Gavrilyuk also wishes to thank his colleagues at the University of St Thomas – Philip Rolnick, Terence Nichols, Peter Feldmeier and David Penchansky – for their valuable comments on the Introduction and other parts of the book. The editors would also like to acknowledge the contributions of Brian Daley, Scot Bontrager, Philip Endean and Derek Neve to the consultation discussions. Mark McInroy, who contributed two chapters to the volume, is also principally responsible for the production of the indexes. Translations are by the contributors unless otherwise stated.