This volume is a collection of essays originally written for a conference held at the Sorbonne in 2011. The subject matter, the Christian adversus Judaeos dialogues, has been much discussed, in the main as part of a wider debate about the nature of Jewish-Christian encounter in antiquity and the Middle Ages. In this vein one of the central questions put to these texts by scholars concerns the extent to which they reflect actual encounter between Jews and Christians or are little more than artificial constructs, written for internal use, in which the Jew becomes a mere foil for Christian catechesis and related matters. In a context influenced by the so-called ‘linguistic turn’ in which the relationship of texts to a mooted external reality has become an ever more controversial subject, this question, long a subject of debate, can appear more urgent than ever. All of the essays, in different ways, engage with this perennial problem.

The contributions divide themselves up into sections devoted to Justin Martyr (unsurprisingly, as Justin wrote the first extant anti-Jewish dialogue, the Dialogue with Trypho, though it is probably the case that the earliest of these works was the Dialogue of Jason and Papiscus, first mentioned by the pagan Celsus, as recorded in Origen's Contra Celsum, and possibly written very soon after the Bar Kokhba revolt in the mid-130s), the dialogues in late antiquity and the Middle Ages. This trinity of sections is book-ended by an introductory chapter by Sébastien Morlet on the dialogues, looking at questions of origins, characteristics and the problem of reference, and by an epilogue by P. Bobichon, examining the development of the dialogue form from the fourteenth to the eighteenth century.

Most of the contributions are of a high standard, mixing specific textual analysis with more general discussion. On the central question of the realism or otherwise of the dialogues, with a few exceptions (Munnich on Justin, negatively, and Boudignon on the seventh-century Doctrina Jocobi, positively), most are reluctant to endorse a straightforwardly unambiguous answer to the question at hand. In one of the subtlest and clearest pieces, Pierluigi Lanfranchi thinks that it is possible on occasion to imagine a kind of reality behind these dialogues, and shows this, at least for Egypt in the fifth century, by analysing places in the letters of Isidore of Pelusium where the reality of encounter with the Jews seems clear, not least in the context of exegetical discussion. In his view the adversus Judaeos dialogues could have provided their readers with models of the way in which to conduct discussions with a potentially hostile Jew (a point partially endorsed in Patrick Andist's discussion of the anti-Jewish features of Cyril of Jerusalem's Catechetical lectures). This, of course, does not mean that such dialogues constituted transcriptions of actual discussions, though on occasion this view might be supported, as might have been the case with the Dialogue of Jason and Papiscus, a point made by Laetitia Ciccolini, in a fascinating piece on Celsus' otherwise unknown letter to the Bishop Vigilius, preserved originally as a letter of Cyprian, one section of which is devoted to a discussion of Celsus' translation into Latin of Jason. What is most interesting about this letter is not so much what it tells us about the dialogue itself, but the fact that it seems to hint at a use of the latter which is bound up with the salvation of the Jews. Here we have a rare glimpse of something about which very little is known, namely the use to which adversus Iudaeos dialogues were put (a problem closely connected to our inability to reconstruct the contexts which provoked these texts). Sometimes, as Mickaël Ribreau shows in his contribution on Pseudo-Augustine's Altercatio Synagogae et ecclesiae, such texts can have anti-pagan purposes rather than anti-Jewish ones. The view that these texts had an inner, catechetical use is discussed by Patrick Andrist, in his piece on the anti-Jewish elements of Cyril's Catechetical orations, though his conclusions as these relate to adversus Judaeos dialogues are cautious. Also relevant to this discussion is Vincent Déroche's absorbing piece on the later Byzantine usage of John Chrysostom's Homilies against the Jews in the seventh-century Kephalaia epaporetika. He concludes that we should not make glib distinctions between the internally-oriented catechetical works and the, externally oriented polemical ones. His essay acts to some extent as a kind of summary of the generally cautious tone of the volume.

Mention of the reuse of material from adversus Judaeos dialogues raises the important point that many of these texts appear repetitive in their content, that is, they often refer to the same arguments and tropes irrespective of their variant contexts and dates. A number of contributors mention this point (see, for instance, Bernard Pouderon's contribution on Justin) and ostensibly it would appear to detract from the idea that these dialogues refer to actual encounters, rather than staged ones. This, of course, seems at first sight to be a sound observation, though it should be noted that such a genre may have been inherently conservative – after all, argument between Jew and Christian centred on a set of well-known themes, mainly of an exegetical kind, making repetition inevitable, and so not necessarily rendering the presence of the latter an indicator of an unreality (see especially the essay by Lanfranchi and that by Claudio Schiano on Nicholas of Otranto's Dialogue against the Jews), just as the presence of an apparently new argument need not be proof of some real encounter. In this context it is interesting that a number of the contributions on medieval dialogues play up evidence of development in the contents of dialogues, not least in the fourteenth century when Christians began to become aware of the content of rabbinic literature (see the essays by Gilbert Dahan and Claire Soussen). Dialogues also became less common as time went on, as Christians began to engage in public disputes with Jews, both points emphasised by Bobichon in the final essay of the volume.

Much more could be said about this erudite and thought-provoking volume. Above all else, and through a variety of examples stretching from the second to the eighteenth century, it makes plain the complexity of the subject and the need for a discussion, which largely eschews adopting an either/or answer to the major question under consideration. Such sobriety, often nuanced and subtle, seems a justified response to the texts under consideration.