Many medieval scholars perceive canon law much as James Thurber described that epitome of evil, the Todal, in his book The 13 clocks: ‘(It) smells of old unopened rooms’, and ‘feels as if it had been dead at least a dozen days.’ The field is intimidating with its own jargon and a complicated referencing system that rivals that of scholastic theology. Yet this was a system by which people lived. It governed their lives and informed their beliefs. The study of canon law, formidable as it is, tells us much about everyday life in the Middle Ages.

Izbicki makes medieval canon law regulating the beliefs and practices of the central Christian ritual of the eucharist not only approachable, but interesting. He moves from canon law as collected in the great compilations of the eleventh and twelfth centuries to the scholastic commentaries on those collections down to the implementation of those high ideals in actual parish visits. It is quite a tour de force on a subject that has received little attention from scholars. Apart from Ian Levy's introduction, ‘The eucharist and canon law in the High Middle Ages’, in Ian Levy, Gary Macy and Kristin Van Ausdall (eds), A companion to the eucharist in the Middle Ages (Leiden 2012), little has been written on this very important topic.

Izbicki begins with an indispensible guide to the canon lawyers themselves. The reader will find herself drawn back to this useful reference often as she gets lost among the thicket of references necessary to the field. Chapter i continues this helpful guide for the uninitiated by gently walking the neophyte through the major collections, papal statements, synodal statutes and finally pastoral guides that addressed the administration and theology of the sacrament.

Chapter ii treats of the real presence and that trickiest of theological concepts, transubstantiation. Canon lawyers considered themselves theologians in their own right despite some protests by university theologians. In reality, the two fields intertwined and it should not be surprising to find that canon law contain a rich source of theological reflection on the eucharist. Canonists, as one might expect, insisted on a belief in the presence of the Risen Lord in the bread and wine and discussed the complications and difficulties associated with such a claim. Canonists were ambiguous about transubstantiation, understanding that term to cover a variety of possible explanations of the change necessary to make the Risen Lord present in the sacrament. Not all explanations were acceptable, however, as the condemnations of Wyclif and his followers demonstrated. Most pastoral guides did not venture into this thicket, but merely affirmed that a belief in the real presence was necessary

Particularly after the Fourth Lateran Council's pronouncement on the topic, a priest was considered the only ordained office capable of effecting the change in the eucharist, although as Izbicki points out, ‘The canon law was slow to adopt a theology of the priestly ability to consecrate the Eucharist’ (p. 68). Wheat bread and grape wine with added water were the proper materials to use in celebration of the eucharist, although other materials were presumably used because they were specifically condemned (milk, grape juice, vinegar, spoiled wine, spiced bread, water, rose water, apple or pomegranate or apple wine). The debate between the Western Church's use of unleavened bread and the Eastern Church's use of leavened bread also made its way into canonical literature with most writers accepting that either use was legitimate.

In chapter ii Izbicki tackles two important practical issues: exactly what words should be used to consecrate the bread and wine, and, more important for the laity, how should the priest properly elevate the consecrated host for the devout gaze of the faithful. Great care was taken down to the parish level to ensure that the priest pronounced the words of consecration fully and properly in order to effect transubstantiation. Starting in the twelfth century, the elevation of the consecrated host and the consequent devotions associate with it became the major form of eucharistic participation by a laity that seldom received communion. Canonists provide great detail to parish priests as to the proper height, duration and reverence shown at the elevation. Particularly to be avoided was the accidental elevation of an unconsecrated host which would lead the congregation into unwitting adoration of mere bread. The congregation was to be alerted to the elevation by ringing of bells and care was taken at visitations to ensure that each parish had the required bells to do so. If canonists insisted on proper devotion by the faithful, they also warned against heretics who denied, or appeared to deny, that the Risen Lord was really present in the consecration raised up at the elevation.

Chapter iii treats of reception of the sacrament. Canonists were quick to point out that the salvific effect of the eucharist could be attained by spiritual communion as well as actual reception. This was a very important point, as actual physical reception of the elements was a rare, usually annual affair for the laity. The laity received only the bread and not the wine, although this became a contentious issue for the Bohemians in the later Middle Ages, some of whom demanded reception under both species for the laity. Since reception was infrequent, canonists and parish manuals stressed the importance of worthy reception at Easter, a duty mandated by law and enforced strictly in parishes. Indeed, as Izbicki points out, ‘Easter Duty could be understood as defining a parish, including its membership’ (p. 170). Mirroring the duty to receive was the obligation on the part of the priest to refuse communion to public sinners or excommunicates, a topic of much interest to canonists.

Chapter iv concerns laws requiring the safe custody of the consecrated bread reserved for taking communion to the sick and dying. From university canonists down to the level of archdeacons making parish visitations there was an insistence that the bread be kept fresh and safe from rodents and especially from those wishing to steal the hosts for use in magic. Detailed legislation described how the viaticum was to be taken to the sick with reverence and devotion. Legislation even existed on what to do if the person were too ill to receive, or if they vomited up the consecrated host.

The great feast of Corpus Christi came to play a prominent devotional role in the later Middle Ages, and, as one might expect, the proper celebration of the feast drew the attention of the canonists. Chapter v turns to the promulgation and spread of this feast. Oddly the concomitant phenomenon of miracle hosts drew little attention from the canonists who seemed on the whole to be sceptical of such claims and who clearly condemned the idea that any appearances of blood or flesh might be that of the Risen Christ.

The material that Izbicki brings to light in this book offers a host of valuable information on the everyday devotional life of medieval Christians as they celebrated the central ritual of their religion. Any scholar of the great medieval drama will find this book an invaluable source for uncovering the rich religious life of a millennium of western civilisation.