This collection of essays, some previously unpublished, covers three related and much contested topics: Jewish-Christian relations (chapters ii–ix), Jewish Christianity (chapters x–xi), and Judaism in the second century (chapters xii–xiii). The four chapters under the latter two headings are all substantial, and make up nearly half the length of the book.

So closely related are the three topics that this work might conceivably have been presented as a monograph rather than an essay collection. Thus, as Carleton Paget points out in his excellent introduction, one's view of Jewish-Christian relations will impact upon one's view of Jewish Christianity, and vice-versa. If a ‘parting of the ways’ model of Jewish-Christian relations is adopted, the ongoing existence of a ‘Jewish Christianity’ may come to seem increasingly anomalous and anachronistic. On the currently influential anti-essentialist account, on the other hand, ‘Jewish Christianity’ discloses the reality of porous boundaries between communities that, at least into the fourth century, were never as clearly demarcated as some ideologues maintained. Indeed, the call for separation represented by the Christian adversus Iudaeos literature may be read, against the grain, as evidence that separation was anything but clear at the level of social reality. Far from merely reasserting an already established boundary, this literature is in the business of constructing a boundary that does not yet exist. Equally relevant to the issue of Jewish-Christian relations is the nature of Judaism in the second century, a period for which texts are surprisingly scarce. Are we to see the dominant development in the Judaism of this period as the formation of an inward-looking, defensive rabbinic orthodoxy? Or, taking a lead perhaps from archaeology, should we suppose that many Jews continued to engage positively with their non-Jewish environments, and that the disastrous revolts in Egypt and Palestine did not necessarily shape all Jewish experience for generations to come?

Closely related though these themes may be, Carleton Paget does not rework his essays into a monograph but allows each to stand as a freestanding entity. The reason is that, from the author's perspective, there is no overall case to argue, no finely balanced synthesis that would do justice to all the evidence. To attempt such a thing would be to repeat yet again the error of seeking to generalise on the basis of incomplete, ambiguous and strictly local evidence. How far does the building of an impressive synagogue really indicate a positive relationship between Jews and their non-Jewish neighbours? (Impressive synagogues were not lacking in 1930s Germany.) Carleton Paget's project is to show that ambiguous fragments are and must remain just that, and that a principled scepticism is a necessary corrective to synthetic accounts and linear narratives that reflect our own priorities and sensitivities more than those of the early centuries of the Common Era.

According to one such narrative, most Jews were concerned purely to maintain their own distinctive cultural identity and engaged neither in missionary activity among idolatrous Gentiles nor in controversy with Christians about scriptural interpretation. Thus the Jew in a text such as Justin's Dialogue with Trypho is a Christian construct that reflects the importance of scriptural interpretation in the Church's proclamation to non-Jews, rather than real-life debates with actual Jews. Such debates might imply a competitive relationship between two proselytizing religions, and so come into conflict with the dogma that ‘Christianity’ (sic) is a ‘missionary religion’ whereas ‘Judaism’ (sic) is not. Precisely because such views are currently fashionable, Carleton Paget urges caution and a willingness to allow the dogma to be challenged by the evidence, such as it is. Why does it seem unthinkable that, within a particular milieu, some Christians and Jews should have argued about their respective truth claims and competed for converts? Here again, though, we should be careful not to generalise, as if all Christians and all Jews could be expected to act in broadly similar ways. On the Christian side, the author of the Epistle of Barnabas polemicises vigorously against Judaism, even arguing that physical circumcision was demonic in origin. Yet, a few decades later, Clement of Alexandria shows remarkably little interest in anti-Jewish polemic. Self-definition over against Judaism was clearly necessary for some versions of Christian identity but not for others. On the Jewish side, there is the much-discussed riddle of the Testimonium Flavianum. Here Carleton Paget draws attention to the questionable role played by presuppositions about what a Jewish writer in late first century Rome ‘could’ or ‘could not’ have said about Jesus and the origins of the Christian movement.

Carleton Paget's distinctive brand of corrective scepticism is informed by an often encyclopaedic knowledge of the history of research in a particular area – for example, that of ‘Jewish Christianity’ and the ‘Ebionites’, to which two lengthy chapters are devoted. The methodological assumption here is that a problem can only be satisfactorily addressed if we can retrace the steps by which the issue has been problematised, perhaps over several centuries of debate. Precisely in retracing that history of research, however, we may find that it brings to light complexities which we are simply not in a position to disentangle. In the case of the Ebionites, the outcome of the history of research so far is that it has served ‘to clarify the difficulties connected with their study rather than to solve them’ (p. 376). That claim, marking the conclusion of a chapter over fifty pages in length, may perhaps be taken as representative of the scholarly ethos of this book as a whole.

Some readers may feel that the scepticism is overdone and that, in some cases at least, agnosticism in the face of complexity need not be allowed to have the last word. Yet the whole field of Jewish-Christian relations is at present peculiarly vulnerable to ideologically-motivated claim and counter-claim, with attendant simplifications and distortions. There is much to be said for an approach which systematically reopens questions generally regarded as closed.