Zehnder, David J. A Theology of Religious Change: What the Social Science of Conversion Means for the Gospel. Eugene, Oregon: Pickwick Publications, 2011. xxii + 179 pages. ISBN: 978-1-61097-359-5.

Religious conversion is a topic of interest to many domains of knowledge. Historians, social scientists, philosophers, and theologians of every creed have studied and attempted to explain conversion. David Zehnder is the rare theologian—or scholar of any discipline—who has done the difficult work of crossing disciplinary boundaries to bring back the fruits of disciplines not his own. The title of his book, A Theology of Religious Change: What the Social Science of the Conversion Means for the Gospel indicates that Zehnder is a net importer of ideas, and contributing back to the social sciences is not on his agenda. He is interested in the pastoral, apologetic uses to which social scientific findings can be put. But his primary task is to mine the psychological and sociological literature on conversion in an attempt to resolve one of theology’s most longstanding questions: “the problem of why one person believes the gospel and another does not” (141).

This “theologian’s cross” is the question of how to reconcile the human and the divine role in salvation. Zehnder’s study of divinity has given him a firm position on the question of God’s role in salvation. He subscribes to a theology of monergism—the belief that God is the only active agent in salvation—that initially drew him to the theological question of predestination, and which shapes the opening and concluding chapters on theology as well many of the observations about the social science of conversion in the middle five chapters.

But Zehnder is also willing to study the human side of conversion, and has set upon the social sciences, especially sociology and psychology, as the best way to approach questions. Reconciling the social sciences and theology requires a theory of how those domains of knowledge relate to one another. This book takes a “correlational” approach that “holds theological and scientific claims in tension as different explanatory means that cannot directly contradict one another” (xv). This theory has its merits, but Zehnder is unable to consistently follow it because he does occasionally find that social science contradicts his theology.

Chapters two through six, which present the findings of social science on various topics, all follow the same pattern. A brief theological or pastoral introduction is followed by an extensive review of social scientific literature, after which Zehnder reflects on the use of the social science for pastoral concerns and its implications for theology. The book summarizes social scientific research on religious change, transformations of individuals, parental influences, ideology, and social ties as they relate to conversion. These summaries of social science read like so many literature reviews, though the book is at least more readable than many of the studies it summarizes. More problematic is the tendency to treat most research as equally valid, which flattens out the debates and disagreements within social science. But it is in his pastoral reflections on social science that Zehnder offers his most useful contribution.

The book’s contributions to theology are more troublesome. The assumption of monergism forces Zehnder to depart from his “correlational” model whenever the findings of social science contradict that central tenet. In chapter three, he correctly concludes that most social scientific research concludes that conversion is “activist”—that is, that people who convert tend to be “active seekers.” This poses a problem for both Zehnder’s method and his theology: “The active conversion is probably sociology’s most direct challenge to monergistic theology which holds that conversion is not . . . ‘a personal accomplishment’” (52–53). For Zehnder, this raises the question “whether active seekers could think that they have chosen the gospel out of a pure act of will and still have the gospel at all” (53). To his credit, Zehnder tries to take a middle road on this question, but still calls the church to action: “the church cannot view active conversion as a normative viewpoint . . . and must continually offer its corrective” (54).

This conclusion is unsurprising and unobjectionable, if one accepts the premise of monergism. But for any Christian tradition for which monergism and election are not the central preoccupations, the question is not a live one and an opportunity has been missed. A more rigorous application of Zehnder’s own correlational model would have found much more use in social science’s findings about active conversion.

In sum, readers who are not concerned with the theological problems implied by monergism, or who are inclined to see salvation as a human choice as well as a divine choice, are not likely to find the theological issues discussed in this book to be live questions. Readers who are inclined to agree with Zehnder that theology is a divine choice will find Zehnder’s theological reasonings informed by social science to be intriguing. I hope they will also find them salutary, for Zehnder’s willingness to approach both sides of the question should be applauded. And all readers can find his desire to turn “theology’s attention away from unsolvable mysteries and toward the question of how the church can communicate to people’s needs” (141), as well as his helpful suggestions to that end, to be profitable.