New Testament scholars have become increasingly interested in recent years in the relationship between the first Christian communities and other small face-to-face organizations. Collegia, occupational guilds, and cultic bodies, after all, formed intensive localized social networks much like the earliest churches, and they were as important as the family and the city in fostering connection. Kloppenborg's new book marks the culmination of years of study of Greco-Roman associations and comprises a landmark publication about associative life among early Christians. Christ's Association offers a comprehensive comparison of the social communities that formed primitive churches (known especially from passages in the New Testament) with the ancient associations recorded in thousands of inscriptions, papyri, and other texts dating between 400 BC and AD 300.

In Kloppenborg's fulsome study, “associations”—a modern category for small, permanent, and private face-to-face groups (18–19)—provide a heuristic key to unlocking the social conditions of early Christian communities, creating “imaginative possibilities to get us beyond the various impasses and dead ends” of scarce evidence (80). Whether associations were organized along occupational, cultic, ethnic, or familial lines, they fostered networks consisting of lateral and vertical links between members, patrons, and other groups, which ultimately generated social connectivity and a sense of belonging. As the author outlines in the opening chapters, associations inscribed and recorded membership rosters, bylaws, meeting minutes, honorific decrees, and foundation accounts, among other things, which allow for analytical comparison with Christian communities. A comparison of the churches in Corinth, Thessalonica, and Philippi with other known associations (80–96) underscores the heterogeneous flavors of early Christ communities in social, economic, ethnic, and occupational composition.

The chapters in Christ's Association largely explore individual facets of associative life. Chapter 3 considers how knowledge of cultic associations and occupational guilds sheds light on the size and meeting places of Christ assemblies: if guilds and cultic groups are any indication, then the first churches must have been very small (fifteen to thirty members) and met in a range of spaces. Chapter 4 explores how the practice of naming members in published rostra (alba), together with other common rituals (e.g., meetings, meals, and processions), defined the group and fostered belonging—much like the first Christian communities defined their membership. Chapters 5 and 6 evaluate the economic levels and social status of early Christians to underscore the relatively greater value of social connectivity and capital in conferring prestige, recognition, and honor among non-elites. Chapter 7 studies how regular meals defined associations as a group, underscoring the equality of members while simultaneously creating occasions for conflict and competition of the kind evident in the Corinthian church. Chapters 8 and 9 deal with collections and funerals, which were both essential functions of associations and reinforced the value of group membership and connection. Two chapters round out the book, one exploring the ways that Christian assemblies adopted democratic language to emphasize their otherness and their citizenship (chap. 10) and another applying the model of associations to the growth of Christianity (chap. 11): new recruits came through a flow of overlapping occupational, familial, ethnic, religious, and commercial networks.

My brief summary does not do justice to the stimulating and provocative character of this work. The book constantly invites the reader to think more comprehensively and deeply about early Christian communities through the lens of hundreds of tiny ancient social groups and clubs that created membership lists, eradicated their delinquent members, issued bylaws, and mandated attendance at their meetings. The social structure and dynamic activities of these associations should open up new horizons for any student of the early church to reimagine Jewish and Christian communities living alongside other private social, religious, and kinship groups in the ancient city. I found the exercise of analogical thinking helpful in expanding my understanding of the specific community problems that appear in Pauline epistles, such as Corinthian conflict over meals, the Jerusalem collection, and the loss of wayward members. The details themselves offer endlessly fascinating tidbits about group activities, such as the typical foods and the amount of wine consumed in group banquets.

At the same time, the author's provocative arguments invite pushback and evoke questions. A functionalist reading of associations, for example, sheds light on how new recruits were attracted—through the benefits of affective ties, belonging, and social connectivity—but tends toward a reductionism that undervalues belief (323–327). We should question the author's frequent assumption that our extant evidence is more or less an accurate reflection of original variety. Should we really be confident, for instance, that the first Christian communities did not generally include the rural poor simply because they are not named in the handful of New Testament documents we have (181; that view has been rightly questioned in Thomas Robinson's Who Were the First Christians? [Oxford, 2016])? How much confidence can we place in estimates of the number of elite in the early church— “maybe even an equestrian or two” before the mid-second century, “less than one hundred” elite in the third (187)—given the fragmentary corpus of literary, epigraphic, and archaeological evidence (outlined at 51–54)? The problem of representation is acute in respect to the several hundred inscriptions that form the basis for much of Kloppenborg's comparison with Christian communities but were produced over a span of 700 years in regions thousands of miles apart. Is it fair to infer that the size of the Corinthian Christian assembly could be no larger than fifteen to thirty people, because the average size of cultic groups fall in that range, when less than a dozen of the ninety-two cultic associations listed in the comparison group (table 1) are contemporary with the Corinthian church (126–129)? Likewise, should we discount an eranistic (potluck style) model for the shared meal in Corinth (1 Cor. 11:17–34) simply because it is atypical of extant associations (235)? Such questions encourage further study about the character of associations over time and place as they are compared with Christian assemblies.

Christ's Association is an outstanding study but not a book for beginners—nor one destined for the undergraduate classroom. Yet the work's accessible style, balanced discussion of theory and evidence, and comprehensive coverage of so many topics in New Testament studies should make it an excellent starting point for imagining the organization and operations of Christian communities in the context of the Roman Mediterranean. In that respect, Kloppenborg has provided a rich example of the fruitful cross-pollination of biblical scholarship with wider fields of ancient studies.