The study of the reign of Constantine at all levels remains dominated by the issue of religion. This is, of course, a product of perennial interest in the nature and impact of his own engagement with Christianity, but it also results from the impressive array of surviving texts from this period. These range across a wide variety of different concerns that might, as Mark Edwards argues in this impressive volume, be united under the umbrella term of ‘religion’, including Christianity, Judaism, Platonism, the cult of Mithras, Hermetic literature and astrology. The book does not advance a grand overarching thesis for interpreting these phenomena, and in fact prominently rejects the idea that an explanation can be found in some deep-seated spiritual need of the age. Instead, its aim is to bring together authors, texts and events that, despite their synchronicity in the Constantinian age, are rarely considered together, mainly due to modern disciplinary boundaries. These divisions largely provide the structure for the volume's three parts, with the first (‘Philosophical Variations’) covering material ‘most familiar to the historian of philosophy’ (viii) and the second (‘Religious Plurality’) examining subjects that are usually associated with the study of the history of religions, while the final, longest part (‘Christian Polyphony’) leads us into territory traditionally regarded as the domain of the theologian. This separation of material might seem to run counter to E.’s stated purpose, especially since explicit cross-references are relatively infrequent, yet the subtleties of the individual analyses draw attention to numerous shared sources, approaches and concerns.

The opening two chapters deal with Christian apologetic literature, particularly when it engages with Platonist authors, most notably Porphyry. The focus here is on Eusebius of Caesarea's Preparation for the Gospel, Arnobius of Sicca's Against the Nations and a number of writings by Lactantius. Setting the pattern for much of the rest of the book, E. includes brief information about each author and a discussion of the text's date and circumstances of composition before embarking on the main analysis of the work, proceeding largely in textual order. Ch. 3 surveys different developments and conceptions of Platonism in this period, moving through Plotinus, Porphyry, Iamblichus and Theodorus of Asine, before concluding with Chalcidius, who is termed ‘a Christian Platonist’ (58), and Methodius’ Symposium of debating virgins. The final two chapters of Part I then interrogate different ideas of ‘holiness’: first comes the notion of the pagan ‘holy man’ or ‘wonder-worker’, particularly as described by Iamblichus, together with the account of astrology in the Mathesis of Firmicus Maternus, who, E. suggests, may already have been Christian at the time; after this, the accounts and writings of the ascetics Antony and Pachomius are shown to be much more than Christianized versions of these texts, with E. providing a nuanced view of the relationship between them: ‘This is not to say that the Life of Antony owes nothing to pagan models, but that it stands in a competitive rather than a parasitic relation to them’ (93).

The three chapters in Part II explore other religious practices and traditions, including, in some cases, the problems involved with reconstructing their ideas and popularity at this time. After a consideration of Mithras, Isis, Osiris, Dionysus and others, including deities termed ‘Hypsistos’, ch. 7 looks at works that aim for ‘a transformation of the self’ (137), in which category are placed Manichaean writings, Hermetica, Gnostic literature and, most interestingly, the alchemical texts of Zosimus of Panopolis, identified here as a ‘Christian Gnostic’ (152). Ch. 8 examines Jews and Judaism, including a fascinating exploration of the mystical interpretation of the alphabet in the Sefer Yetzirah, which is compared to the fourth-century Christian On the Mystery of the Letters.

Part III opens with a discussion of Constantine's Christianity, including rejecting the ‘solar halo’ theory of Weiss for explaining his visions, and then looking at his Oration to the Assembly of the Saints and legislation that may have been inspired by Christianity. This is a succinct and clear discussion, although it is not explored as deeply as some aspects of the book, and there were a few notable absences from the bibliography, including Ray Van Dam and Jill Harries. Ch. 10, entitled ‘The End of Sacrifice’, is not only an impressive exploration of Neoplatonist and Christian views of sacrificial rites, but also a well-argued rejection of the idea that the Eucharist could be recognized as ‘a perpetuation of sacrifice as this was known in the Mediterranean world’ (220), except in its social and communal function. After a chapter on the canon and exegesis of Scripture, once again featuring Eusebius prominently, his Demonstration of the Gospel occupies much of ch. 12, which also outlines eloquently how Juvencus' biblical poem, the Historia Evangelica, selected from and adapted the four Gospel accounts. The following chapter is an excellent examination of Pamphilus and Eusebius' defence of Origen and his legacy in the ‘Arian controversy’, including the inclusion of homoousios in the Nicene Creed and Eusebius' criticisms of Marcellus of Ancyra. This provides a deft demonstration of the impossibility of neatly sorting the theologians of the period into categories such as ‘Origenist’, ‘anti-Origenist’, ‘Arian’, ‘Nicene’ or ‘Eusebian’, despite the tendencies of contemporary heresiological discourse. Ch. 14 then concludes the volume by considering Eusebius' positive view of the relationship between empire and Christianity under Constantine, while also exploring the varying perspectives of the Melitians, Donatists, Athanasius, Palladas and Firmicus Maternus.

Throughout this useful volume, the repeated appearances of some of the same themes, issues and authors — and, on occasion, the same texts — in multiple chapters cumulatively invite the reader to appreciate the interconnectedness of diverse forms of literature and practice, and thus to ask whether the designation of them as ‘diverse’ would have been as obvious to readers and authors at the time. Perhaps more importantly, E. also warns against letting superficial similarities between texts become the basis for simple, reductionist statements about the ‘religious identity’ of authors, or seeking to neatly pigeonhole their works within clear intellectual genealogies. This detailed and thoughtful account is a useful introduction to a wide selection of early fourth-century writings and provides a fascinating insight into the innovation, experimentation and complexity of the age.