Karen V. Guth has written an important book about the costs of separation in scholarship and the benefits of substantive engagement across divisions. Writing primarily to scholars in Christian ethics, Guth describes the dynamics of forging one's intellectual work in contrast to other schools of thought. In carving out his or her distinctive path, the scholar often reifies and truncates other approaches and renders unlikely any meaningful engagement with difference. These dynamics (separation, reification, and truncation) do a great disservice to scholarship, teaching, and learning. They also undermine the capacity of scholarship in Christian ethics to serve purposes beyond itself and to address the moral demands of our time, which are many indeed.

Guth advances her argument about methods of scholarship in Christian ethics through a careful exploration of three schools of thought: realism, witness theology, and feminism. One of many compelling features of Guth's text is that it takes seriously the merits of the practices and positions she finds problematic. Guth carefully delineates the arguments that constitute the boundaries around these different approaches to Christian theology and ethics. But she makes her case for the costs of separation by demonstrating its impact on scholarly engagement with three formative figures in American Protestant ethics: Reinhold Niebuhr, John Howard Yoder, and Martin Luther King Jr. In each of three chapters, Guth explicates criticisms launched from different directions toward these figures (for example, from witness theologians toward Niebuhr, from realists toward Yoder, and from womanists and feminists toward King). She works with these criticisms in a remarkably nuanced way, noting the truth within them and carefully documenting the places where the critics have dismissed, misrepresented, or overlooked things that do not conform to the criticism. Guth then practices the very kind of engagement that she calls for, drawing on Kathryn Tanner's “genuine community of argument.” For each figure, she identifies an agenda item that emerges when one utilizes the critical concerns in more constructive ways. Thus, the points of contention—which remain clear—provide traction to take discussions of these well-known figures in new directions.

Christian Ethics at the Boundary is a complicated text, and readers will be grateful for Guth's clear organization and prose. She is working with arguments on several levels: differentiating methods of scholarship, tracking disagreements historically, considering particular criticisms of familiar figures, working constructively to map new conversations, and making a case for the relevance of Christian theology in a hurting world. These points and purposes cohere, but they make for a complicated text better suited to advanced study in ethics than to introductory courses. While she explains ideas and arguments fully, Guth does assume knowledge of the figures and schools of theology and ethics she explores. The book would work well in advanced ethics courses where students have received an introduction to Niebuhr, Yoder, and King, or to the approaches of realism, witness theology, and feminism. Guth's text would certainly be a welcome addition to any course where one intends to engage contemporary critics of these formative figures in substantive ways. On this point, special mention of Guth's treatment of Yoder is warranted. As documented in the lengthy footnote in the introduction, there is now public acknowledgment of Yoder's sexual violence toward women over many years. Guth notes in an unflinching way Yoder's crimes and “profound failures to personally embody feminist ideals,” but she does not obscure the presence of those ideals and commitments in his writing. Indeed, Guth powerfully argues that Yoder's violence toward women makes it imperative for witness theologians to fully develop “an account of feminism as Christian politics.” Here and elsewhere, Guth does not aim for agreement, but works constructively with argument, thus modeling the approach to scholarship that she commends.

For those of us in the field of Christian ethics, whether we are senior scholars or doctoral students, Christian Ethics at the Boundary is a must-read. With astute observation, fresh insight, and a crucial claim about the larger purposes of scholarship, Guth reminds us why we must participate in communities of argument.