Gratitude is a true privilege. We often speak of a “debt of gratitude,” and the debt of gratitude I owe for this work is enormous and widespread. But one of the points of this book is that living virtuously is life-giving for all involved. I can only hope that the following people have found the interactions which constitute their contribution to this book even a fraction as life-giving as they have been for me. It is a privilege to acknowledge my indebtedness in gratitude to the following.

I would first like to thank the students from my classes for whom this book was written, and who have shaped its entire content with their questions, contributions, and wonderful conversations. The book is truly the percolation of these classes and so would not be possible without the students. Many students were particularly generous in giving me explicit and written feedback on earlier versions of the text. With apologies to any I may have missed, special thanks to Alex Bautz, Liz Casey, Marian Cassilly, Mary Cohill, Mel Corley, Laura Davidson, Wil Donahue, Emily Dufficy, Rachel Dunphy, Mark Fellin, Ryan Frederickson, Philip Ilg, Rachel Jacobs, LeighAnne Kauffman, Peter Mercatanti, Kaylie Metz, Caitlin McKeon, Ellen Rawson, Dimitrie Samata, Emilee Senkevitch, J. Silverman, Lynne Simmons, and Kirsten Toth. Teaching assistants Matt Haven and Donna Moga also provided valuable feedback.

Many colleagues in the field of moral theology were generous in helping to shape the course out of which this book grows, and/or commenting on earlier versions of this text. Special thanks to David Cloutier, Tom Leininger, David McCarthy, John Grabowski, Bill Barbieri, and Jim Halstead. Friends at New Wine, New Wineskins, the annual symposium at Notre Dame for pre-tenure Catholic moral theologians, have also made important contributions in more ways than one. I cannot fail to mention the three mentors who have been so generous with me throughout my own formation in moral theology, and without whom I would never have been able to take on this project: Jean Porter, Servais Pinckaers, OP, and James F. Keenan, SJ. In terms of publishing and editing this book, Jeremy Langford and Rodney Clapp have been indispensable. I am grateful for their diligent work and especially for their friendship. Chris Blake and Mount St. Mary’s University generously provided grant money, in addition to a wonderfully hospitable intellectual environment, for the development of this book. Friends at Georgetown University’s Office of Campus Ministry also provided a home in Healy Hall for the writing of this book. Finally on the professional side, it seems fitting to thank those whose work has been so formative on my teaching this course and thus writing this book. It is ludicrous to thank such cornerstones of the tradition as Augustine and Aquinas, and even those more recent intellectual giants such as Josef Pieper and C. S. Lewis who have gone before us. But it does seem appropriate to acknowledge contemporaries such as Robert Barron and Paul Wadell, whose works have been models of how to teach the riches of the Christian tradition to undergraduates in an accessible and attractive manner.

Lastly I would like to express my gratitude to those people who, while all intellectuals in the best sense of the word, have influenced me and therefore this work not primarily through their intellectual activity per se, but through the witness of their lives. My own vocation to study and teach moral theology has been born from the faith and love of these people who taught me through their examples how a life of virtue in Christ is indeed a truly fulfilling life. First mention must go to my wife Courtney who constantly teaches me about the virtuous life, in ways she does not describe with theological terminology but nonetheless speaks more vividly in her actions. Teachers and friends Stephen Balletta, SM, Otto Hentz, SJ, Timothy Scully, CSC, Sean McGraw, CSC, Lou Delfra, CSC, Brian Daley, SJ, and Cathy Kaveny have all helped teach me the content of this book with their lives and friendships, and for each of them I am eternally grateful.

Perhaps the best example from my own experience of people teaching with their lives has been that of my parents, Joan and Bill Mattison. With no theological training whatsoever, they are nonetheless the people in my life whose faith and love are so constitutive of who they are that they taught me more than anyone what it means to live a life of Christian virtue. In more ways that I can mention here or even perhaps recount, I owe the good things of my life to them. And thus it is to them that this book, a small token the life they have borne in me, is dedicated.