This book is an ecumenical commemoration of the 500th anniversary of the Lutheran Reformation, featuring essays by Catholic and Protestant scholars from Europe and the United States. It came out of an international conference held at the Pontifical University, St. Patrick's College, Maynooth in May 2015. The essays vary considerably in topic and perspective, but the unifying theme is Lutheran-Catholic reflection on the meaning and significance of the Reformation today. The four sections of the book provide a helpful structure for the individual essays: “Historical Foundations,” “Luther and the Medieval Tradition,” “Luther and Catholic Theology,” and “What Can Catholics Learn from Luther?” As the section titles indicate, the purpose of these essays is not only to remember the Reformation but to engage in ecumenical dialogue with the hope of gaining new insights through engagement with the other. As such, it builds on previous dialogues and documents (especially the Joint Declaration on the Doctrine of Justification and the more recent From Conflict to Communion: Lutheran-Catholic Common Commemoration of the Reformation in 2017).

In order to provide a representative sample of essays from this collection, I will discuss one from each of the four sections. In the “Historical Foundations” section, Heinz Schilling's essay “1517—A Landmark in World History?” addresses this question by moving beyond what he describes as the “Europe- and Protestant-centric perspective” (5) identified with Hegel, Weber, Jellinek, and von Harnack. He opposes a Protestant-centric view by describing parallel reform movements in the Catholic Church, exemplified by Charles V's Christ piety and the biblical reform centered at the University of Alcalá. (While acknowledging the difference in impact when compared to Luther, he downplays that, as well as their significant theological differences, in order to emphasize common roots of reform.) He opposes a Europe-centric view by discussing other significant events in world history: the European encounters with Mayan and Chinese civilizations and the dominance of the Arabian Peninsula by the Ottoman Turks. Schilling is therefore opposing an extreme version of the significance of the posting of the Ninety-Five Theses, as revealed by his concluding remarks which call for the recognition of other significant world events and the contributions of Roman Catholicism to modernity while ascribing “extraordinary meaning to the process that started on 31 October 1517” (11).

In the section “Luther and the Medieval Tradition,” Philip Cary offers a rather provocative argument in “Luther and the Legacy of Augustine.” He points out that Luther's distinction between law and Gospel is developed from Augustine's distinction between law and grace, but Cary goes on to argue that Luther's version is “more Catholic than Augustine” (39). This is based on Cary's claim that Luther's appropriation of medieval sacramental theology led to his understanding of the Gospel as “an external means of grace, having a kind of sacramental efficacy” (37). This is reflected in an essential difference between Luther and Augustine: while Augustine calls for a prayer for grace, Luther affirms a promise of grace which “gives what it signifies” (51).

The third section, “Luther and Catholic Theology,” continues this reassessment of the relationship between the two. In this section, James Corkery's essay on “Luther and the Theology of Pope Emeritus Benedict XVI” focuses on Cardinal Ratzinger's 1983 interview, “Luther and the Unity of the Churches,” to first describe affinities between him and Luther, then nuances of difference, and finally genuine differences. Corkery locates their affinity in an experiential, personal approach to theology and the recognition that the Christian life is “gifted” by God. However, there is a nuanced difference in their language about “faith” and “love” so that Ratzinger can allow for love to play a role in salvation but only in its relationship to faith. Corkery describes the genuine difference in terms of ecclesiology and specifically Ratzinger's rejection of Luther's “radical personalization of the act of faith” in contrast to his own conviction of the centrality of the church (135). Lutherans, of course, could point to the vital role of the church for Luther in proclaiming the Gospel through Word and Sacrament, but they would acknowledge a fundamental difference in Ratzinger's view of the church as defined by apostolic succession and the Eucharist. Corkery ends by inviting the reader to evaluate whether Ratzinger has slowed the progress toward Christian unity or simply set realistic goals in the process of ecumenical dialogue.

The title of the fourth and final section— “What Can Catholics Learn from Luther?”—is not entirely accurate. Both Gesa E. Thiessen's essay “Luther and the Role of Images” and Christine Helmer's essay “The Common Priesthood: Luther's Enduring Challenge” explicitly offer lessons for both Catholics and Lutherans. Thiessen concludes that Lutherans and Catholics share a common appreciation for art in the context of worship (particularly in contrast to churches that have traditionally rejected them) and that the challenge they both face today lies in “promoting images that are life-enhancing, while not being shy to question images that promote the antithesis of fundamental human and Christian values” (186). In her essay, Helmer argues that Luther's notion of the common priesthood was focused on preaching and embodied in the family and does not represent an alternative ecclesial authority to the Catholic priesthood. She concludes that Luther's view challenges a Protestant understanding of common priesthood defined in opposition to Roman Catholicism at the same time that it calls the Catholic priesthood to continual critique and reform.

This collection of essays models ecumenical dialogue that does not minimize differences or disagreements but seeks to learn from the other tradition. It serves as a fitting and hopeful commemoration of the 500th anniversary of the posting of the Ninety-Five Theses and the dramatic events that followed.