The past fifteen years have witnessed several major studies of Christian debates concerning the theology of angels, their representation, and their ritual veneration.  Arnold's book joins the list, but the author is not a latecomer to the conversation. His 2000 article on the Michael shrine at Monte Gargano is frequently cited in studies of angels.  The book under review has its origins in Arnold's 1997 dissertation on the cult of Michael, but the 2014 publication demonstrates a thorough command of more recent scholarship. Indeed, the book's collection of secondary scholarship will be of use to students and scholars researching angels in late antiquity. The book traces Michael the archangel's path from a potentially heterodox object of veneration among pagans, Jews, and Christians in the first centuries of the Common Era to his role as a powerful symbol of Nicene Orthodoxy and Imperial Victory in Byzantine Italy and the Carolingian West. The most valuable and original contributions are the book's chapters dealing with Monte Gargano and its impact on other Michael shrines in Western Europe. The book's chapters dealing with eastern Mediterranean and pre-Christian Michael veneration are chiefly a synthesis of previous scholarship, providing a serviceable introduction to the topic.
Arnold begins his study by describing the founding of Mont Saint-Michel, a site that functions as an investigative final destination to which the book returns in its concluding chapter. The description of Mont Saint-Michel allows Arnold to introduce several of the questions the book addresses, embodying as it does, many of the problems and paradoxes of the archangel Michael. To begin with, there is the issue of distinguishing between St. Michael and corporeal, human saints. For example, churches dedicated to the martyrs and the other holy people who made up early Christianity's cult of the saints could claim a physical link to their patron saints through their bones or contact relics. In contrast, physical links with relics of the celestial archangel would seem to be impossible. However, Mont Saint-Michel has such items. How the incorporeal Michael came to be physically linked to a particular site in France via contact relics originating at Monte Gargano in Apulia is one of the stories that Arnold traces in his work. In Chapter 4, for example, Arnold fully recounts the traditions of the relics' appearance--specifically Michael's cape and footprint--in late antique Apulia. As curiously interesting as those details are, however, Arnold rightly stresses the importance of the appearance of the relics of Michael for the cult of the archangel's emergent orthodoxy. Specifically, the appearance relics associated with Michael facilitated the cult's localization within churches and within the limits of Nicene orthodoxy. Michael could thus be celebrated in official church liturgies, and on specific holy days, in a manner analogous to that of the martyrs, as Arnold discusses. Indeed, this reviewer would argue that centuries of inclusion of Michael alongside sanctified humans in the liturgy has resulted in a lack of distinction such that present-day Christians often conceive of Michael and sanctified humans as similar beings operating under the broad typological category of "saint." However, as Arnold argues in the first half of his book, Michael's place among the saints was not always so secure. Rather, as the author describes in the second half of the book, Michael's place in Catholic Christianity came about as a result of specific events and decisions that brought the archangel into the folds of Nicene Orthodoxy in a manner acceptable to church authorities.
Chapter 2 elucidates Michael's role as an "ecumenical" archangel who was popular among Jews, pagans, and Christians. As Arnold relates, in the formative period of early Judaism and Christianity, diverse religious practitioners regarded Michael was a powerful mediating figure worthy of invocation by various means. Arnold draws upon recent scholarship to provide a synthetic overview of how Michael came to be a figure of ritual power among various Jewish groups in the second-temple period, how angels generally came to be objects of invocation in later Roman religion, and the manner in which Michael and other archangels appear on amulets and magical formulas from the period.
Chapter 3 examines specific sites of Michael veneration in the eastern Mediterranean, Michael's association with imperial victory ideology, and Michael's relationship with the Trinity in post-Nicene theology. This is a lot to take on in one chapter, and as a result the chapter is suggestive rather than conclusive. The chapter discusses Germia and Chonae, two of the most popular Michael healing shrines in Late Antique Anatolia, as well as Mamre in Palestine, the Bethesda Pool in Jerusalem, and the Fountain of the Lamps in Corinth. The latter three sites were certainly associated with angels, although not necessarily and certainly not exclusively Michael, a point that the chapter seems to gloss over. I must offer a minor correction here to Arnold's discussion of a lamp from the Fountain of the Lamps. In commenting on a lamp dedicated at Corinth and inscribed with a cross and the graffito "to the angels who dwell upon these waters," Arnold states "maybe a Jew simply used a lamp intended for the Christian market" (41). While the phenomenon of non-Christians using lamps molded with Christian symbols is attested elsewhere, such is not the case with this particular lamp. The cross is part of the inscribed graffito, not a pre-molded symbol, as illustrated in published photographs of the lamp. 
Chapter 3 also attempts to forge a link between Michael's roles as a healer and a symbol of imperial victory, two distinct aspects of the archangel highlighted in Rohland's 1977 Der Erzengel Michael: Arzt and Feldherr.  Arnold finds the connection between these two roles in the stories of Michael as a healer of infirm feet, particularly the story of the doctor of the palace guards, Probianus, and his healing vision of Michael. As Arnold sums up, "The archangel, and his healing of the feet, became a verbal and visual shorthand to communicate a Christian version of imperial victory" (51). This connection is unconvincing and, ultimately, unnecessary for Arnold's otherwise compelling discussion of Michael as healer and Michael as a symbol of victory. Arnold's evidence suggests that these are two distinct traditions about Michael that arose in the formative period of the archangel's cult. It is unclear why a link between these two traditions needed to be made, and the link is unconvincing in any case.
Chapters 4 through 6 discuss the traditional of Michael at Monte Gargano and the arrival of his cult in Gaul. These chapters are the most rewarding of the book, and scholars late antique pilgrimage sites, relics, and ecclesiastical authority will find rich detail concerning the appearance of Michael's cape and footprints at Monte Gargano, the use of Michael to bolster ecclesiastical and temporal authority in early Medieval Italy and Gail, and the emergent distinction between licit and illicit Michael veneration in Carolingian Europe. For example, the book's discussion of Michael under the Carolingians contains a revealing discussion of the Admonitio Generalis of 789's reception of Canon 35 of Laodicea (ca. 360), a canon which banned the invocation of angels outside of the church. As Arnold observes, the Admonitio Generalis confused Canon 35 with the Gelasian Decree and as a result stated that Christians could only call upon Michael, Gabriel, and Raphael. The Carolingian decree thus did not ban extra-ecclesiastical angel invocation generally as the original Canon of Laodicea had done. Rather, it legitimized the veneration of Michael (and the other two biblically attested archangels) while making illicit the invocation of other known or invented angels. The Admonitio is thus representative of the final stage in Michael's path from a liminal figure venerated by divergent religious groups and invoked on magical amulets to one celebrated on official holy days and liturgies and used to support Nicene orthodoxy, kings, and emperors.
Arnold's book will be rewarding for those interested in the early Christian cult of the archangel Michael, but that reward comes at the price of sometimes-difficult reading. For example, Chapter 6 on the Carolingian cultus is rich in detail but it can be so compressed as to read more like research notes. That same chapter betrays some haste in editing by using the same quote from Pope Zacharias on two consecutive pages (124-125). Another issue is the consistent lack of in-text discussions of previous scholarship. The opening chapter mentions Leuken's 1898 study of Michael, but after that the book avoids discussing modern scholarship. The book is not intellectually dishonest. It is amply and annotatively end-noted, but the lack of in-text historiographical discussion makes it difficult to discern the author's ideas from those of previous scholars without turning to the back of the book. An illustrative case is a discussion of representations of Michael and other archangels at Ravenna (82-84). The opinions presented there are drawn from significant scholarly debates about the theology of Arian and Nicene visual programs. However, the body text does not signal the significance of the debate, and the reader would not know about it without turning to the endnotes. Perhaps the choice to avoid historiographical discussions came at the request of the publisher. If so, it is regrettable and should be rectified in future publications in the series.
1. E. Muehlberger, Angels in Late Ancient Christianity (Oxford: Oxford University Press, 2013); R. Cline Ancient Angels: Conceptualizing Angloi in the Roman Empire (Leiden: Brill, 2011); S. Garrett, No Ordinary Angel (New Haven: Yale University Press, 2008); G. Peers, Subtle Bodies (Los Angeles: University of California Press, 2001).
2. J.C. Arnold, "Arcadia Becomes Jerusalem: Angelic Caverns and Shrine Conversion at Monte Gargano," Speculum 75 (2000): 567-588.
3. Cline, Ancient Angels, p. 135, fig. 5.1.
4. J.P. Rohland, Der Erzengel Michael: Arzt and Feldherr (Leiden: Brill, 1977).