John O'Malley, SJ, has made many contributions to church history in the last sixty years. His engagement with conciliar history in particular has marked the latest fifteen years of his scholarly production, beginning with the Second Vatican Council (What Happened at Vatican II [Harvard University Press, 2008]) and continuing with the books on Trent (Trent: What Happened at the Council [Harvard University Press, 2013]) and on Vatican I (Vatican I The Council and the Making of the Ultramontane Church [Harvard University Press, 2019])—a trilogy that has prompted a new interest in conciliar history and on Vatican II in the English-speaking world.

This book, When Bishops Meet, is in some sense the completion and extension of that trilogy on the councils of the modern era: a chronological extension, as this latest book presents a comparison between different kinds of councils (from the beginning of church history until Vatican II); but also a theological extension, in the sense of an actualization of the meaning of conciliar history for the possible role of councils of bishops in the global Catholic Church of today and tomorrow.

In part one, “The Great Issues” (13–81), O'Malley addresses the issue of the councils’ task, of their role in the development of church teaching, and of the leadership in the councils. Remarkable is O'Malley's nuanced assessment of the council of Trent. Far from the black legend of an inquisitorial church, he describes Trent as a step taken by Catholicism toward modernity. The unique role of Vatican II emerges as a council of bishops whose decisions were not mainly about the institutional church, but the conscience of all members of the church. Such decisions, too, came not in the form of judicial rulings, but as formulations of ideals with individual and institutional implications. O'Malley points out the need for the Catholic Church today to address the issue Vatican II could not address: how to make coexist the episcopal leadership (theoretically clear in the teaching) with the need of a collegial and synodal model of government (both theoretically and practically far from clear).

In part two, “The Participants” (85–169), O'Malley addresses different kinds of participants to councils: popes and curia, theologians, laity, and “the other.” One enlightening statement is about “the ambiguity of the pope's relationship to the council” (101), which is accurate not only for Vatican II but also for the conciliar institution per se in the twenty centuries of church history. The most interesting section here is the one on the laity, as it casts a light on the vastly different meanings of “laity” in the span of time between medieval councils (political authorities and their representatives) and Vatican II (representatives of ordinary lay people)—and even more in future perspective. Vatican II, the message and the event, was largely shaped by the attention to “the others”—from an ecumenical, interreligious, and one-human-family perspective.

Part three, “Impact and Future” (173–209), opens with the important statement that “these councils cannot be consigned simply to the category of church history. They were major cultural events” (174). On the effects of the councils, Trent clearly “contributed unwittingly to the development of the confessional state and thereby to the political divide that marked Europe for centuries to come” (182). On the other hand, Vatican I accelerated an ecclesiastical centralization, but also was “an early prelude and stimulant to contemporary global awareness. It helped make Catholics more Catholic” (185). The documents of Vatican II were “an expression of the Church's struggle to come to terms with the modern world while at the same time remaining faithful to a Gospel proclaimed long ago” (192).

The last question addressed in this section, “Will there be another one?”, is particularly important given the fact that in the ecclesial debate there is a reluctance to examine the issue of the feasibility of another general council similar to Vatican I or Vatican II in the future. Here O'Malley helps us understand that the difficulties are more practical (the much higher number of bishops today compared to just sixty years ago) than theological (the participation of the laity would not be a real innovation, given that there has always been a representation of the laity at previous councils). It is not obvious that the next general council will even meet in the Vatican: “That the next council should meet in Buenos Aires or in Nairobi is not unthinkable” (207).

In the conclusion, O'Malley repeats the defining feature of these councils: bishops in communion (albeit in different ways) with the pope, different degrees of participation and control by the Roman Curia, and vastly different degrees of participation by theologians and the laity—male and female. All of this is already something like a list of questions for those who want to imagine the conciliar tradition of the future. For O'Malley, Vatican II constitutes the culmination of conciliar history in the sense of a certain uniqueness: “Vatican II was not a legislative-judicial meeting . . . rather, a meeting to explore in depth the church's identity, to recall and make operative its deepest values, and to proclaim to the world its sublime vision for humanity” (213–214).