The Church in the Modern World: Gaudium et Spes, Then and Now celebrates the fiftieth anniversary of Vatican II by offering a theological interpretation of the council's final document, Gaudium et Spes (GS). Lawler and Salzman, both ethicists, and Burke-Sullivan, an ecclesiologist, pair expertise in these two often separated theological disciplines. Framing their work with the text of GS, these authors situate the ecclesiological, anthropological, and ethical issues raised by the pastoral constitution—issues that in many cases are still contested within Catholicism—within the context and history of effects of Vatican II's final document, with insight for Christians in the world.

Within this ethical/ecclesiological matrix, the book does several things. First, it recounts a story of GS within the longer history of how the church relates to the world. The story narrates a tradition with multiple tributaries that converge in Vatican II in a conflict between neo-Augustinian classicist and neo-Thomist historically conscious schools of thought. That conflict resulted, after an arduous process, in GS. The authors argue that this process, and the historically conscious text it produced, authorize renewed ecclesiologies and theological methods that are sensitive to the changing reality of the “world,” and thus open to change and development in the tradition.

Without ever appealing to “the spirit of Vatican II,” this argument about the meaning of GS is nonetheless a measured, but weighty, volley within contemporary debates on this question. The argument continues via an ecclesiological (chapter 2) and a methodological (chapter 3) discussion. The authors’ presentation of GS's ecclesiology portrays the mission of the church as bringing God's compassion to the world after the manner of Christ. In this work, all the baptized, through the Holy Spirit, discern how best to serve the world in solidarity with the poor. In the argument as it relates to method, particularly for theological ethics, the force of the volley comes from the authors’ case for the legitimacy of a pluralism that arises from the perspectival and historical character of knowledge, which leads to objective, but nevertheless partial, theological and ethical judgments, to which conscience must adhere. The first half of the book concludes with the statement that “Gaudium et Spes … provides a revolutionary evolution in Catholic moral theology to aid in reading the ‘signs of the times’ and the formation of a well-formed conscience seeking answers to the complex questions facing human beings” (110).

In the second half of the book, the authors consider some of these questions as they were addressed in part 2 of GS. They consider marriage (chapter 4), Christian life and the service of love and justice (chapter 5), and the political community and peace building (chapter 6). Each chapter places key issues within extended historical perspectives, which demonstrate how Christian ethical arguments have always been, and continue to be, shaped by bringing Christian sources into dialogue with culture. The concluding treatment of the development of a peace-building tradition in the place of the just war tradition is one such example.

The value of this book follows from its mapping out examples of significant historical development; its argument for why such development is a necessary part of Catholic tradition, including GS; and its transparency in working out how Christians continue to work within that historical process for critical issues today. Throughout the text, the authors never move far from GS's own concerns—the people of God; the affirmation of the formation and exercise of conscience; and trust that the Holy Spirit continues to guide the church in history, for the world.

One question I have for the authors regards the audience. The erudition of the book and its level of detail, both in the context of the council and the discussion of methodological and epistemological issues, suggest a book that is best for advanced students of theology. On the other hand, the material in the second half of the book dealing directly with particular ethical questions, while sophisticated, is less technical, suggesting an audience of interested laypeople in parishes or in undergraduate courses. The fact that each chapter concludes with “questions for reflection” that might be appropriate for a parish study group suggests further that a less theologically educated audience may indeed be the intended audience.