The relevance of Christian liturgy can hardly be underestimated. Christians are present in most of the world’s cultures and societies today. Sometimes they are only tiny minorities. Sometimes these minorities are well respected, but the opposite can be equally true. Sometimes they are suppressed and even persecuted. In other cases Christians occupy a majority position, which enables them to celebrate and live their faith in the public realm. This position, which can but may not necessarily go back several centuries, also allows them to be in power and to staff the decision-making bodies at many levels of socio-economic and political life. Still other historical circumstances cause Christians to look back on an influential past and a lost impact. This often results in a fragmented situation with an uncertain outcome, which obviously comes with many challenges, not least for Christians themselves. This scenario is particularly the case in so-called secular cultures, characterized by sometimes dramatically rapid processes of pluralization and detraditionalization. The point, however, is that Christians in all these different situations have somehow inherited ways of celebrating their faith and continue to develop ritual practices, worship patterns, and a corresponding prayer life. What unites Christians in so many cultures and societies is not so much what and how they think but rather a consistency of a certain liturgical praxis. In a way, liturgy more than doctrinal contents or moral convictions determines Christian identity. The liturgy’s relevance consists in nothing other than constituting the deepest core of the Christian religion.

In the light of these observations, the present Cambridge Companion to Christian Liturgy aims to provide a comprehensive study of the meaning of Christian worship by shedding light on the intriguingly complex history it went through (with a focus on the Mediterranean and European regions, where it has historically been the strongest), the fundamental and constitutive elements of which it consists, its embodiment in concrete practices and artistic expressions, and its unique importance for the life of the Churches, as well as its creative potential for theological thinking and research. The volume deliberately combines a solid introduction into the basics of the liturgy with a wealth of impetuses for independent thinking. It moreover opts for a consistent and synthetic theological approach. This means at least three things. First, it considers liturgy not only from a neutral or outsiders’ perspective or from a mere historical or anthropological viewpoint but also as a reality in close relation to divine revelation and a wide variety of ecclesial traditions. Second, it subscribes to a broad and inclusive vision about theologians actively engaging with other areas of expertise, whereby interdisciplinarity is not a contemporary academic fashion but something actually, and fruitfully, practiced all over the line. Third, it overcomes denominational, methodological, and ideological narrowmindedness by relying on decent academic scholarship and thoroughgoing dialogue among experts.

For there is no reason in denying that, in recent decades, the field of liturgical studies has undergone a rapid development of constructive exchanges with other areas, such as ritual studies, social sciences, gender studies, performance arts, postcolonial discourses, critical theories, socio-economic and moral issues, practical and empirical theologies, and so on. These interactions have achieved many interesting insights and results, and they have undoubtedly enriched the study of Christian worship. At the same time, however, they have also raised the critical question about the specificity of liturgical studies, its primary objects and its methods: What is it that liturgical scholars – with their different capacities and competences as historians, systematicians, and practitioners – can uniquely contribute to the conversation about the meaning and role of Christianity for humanity and the world? Correspondingly, while realizing the deep impact and crucial import of multiple approaches and various discourses in contemporary academia from which liturgical studies cannot stay absent, the present volume first and foremost centers on the specifics of Christian liturgy itself.

The distinctively theological approach for which the present volume opts is made concrete throughout the individual parts and contributions inasmuch as the authors have paid sufficient attention to one or more of several clusters:

1. (i) liturgy as both commemoration (anamnesis) and imitation (mimesis) or, in other words, liturgy as the enactment of past events by way of memorial actions and imitations, implying a distinctive understanding of “time”;

2. (ii) the pervasive idea of “mystery” and the multiple ways in which it is embodied in matter, actions, sounds, texts, images, gestures, and habits;

3. (iii) liturgy as standing at the intersection of an upward movement (anabasis) and a downward movement (katabasis), including human actions directed toward the divine and the belief that God equally works for humankind, or, put differently, liturgy as meant to be worshiping God and sanctifying the world simultaneously;

4. (iv) liturgy as representing – and maybe even illuminating – fundamental tensions within the human condition – for example, between memory and hope, the already and the not-yet, the present and the promise, the actual and the unfulfilled, pain and relief, boundedness and liberation, creation and redemption;

5. (v) liturgy also as incarnating (and undergoing) tensions between reality and eschatological norms – that is, between how things are (lived) and how things should be (ideally);

6. (vi) liturgy as naturally involving various human faculties, including not only the cognitive ones, such as reason and the intellect, but also the imagination, the senses, affections, emotions, passions, and desires.

Furthermore, it is crucial for the set-up of the present volume that certain conceptual and ideological binaries are overcome. Certain debates and controversies over liturgy (e.g., over what is a “good” versus a “bad” service, or over the value of traditional forms) are not avoided but named with a view to clarifying the rationale behind various theories, standpoints, and opinions. The authors of individual contributions, however, do not give evidence of any partisanship promoting one vision over against another one. Rather, they seek common ground in the realization that the one who deals with liturgy deals with a very delicate and deeply human matter, and that people’s attachment to liturgical forms above anything else deserves respect. In other words, ossified oppositions between conservative versus liberal ideas, between liturgy as mere conviviality versus liturgy as solemn ceremony, or between pro and contra inculturation have no place in the present volume. Instead, the authors advocate an open and tolerant view, based on profound academic scholarship, and an overall irenic attitude vis-à-vis liturgical variety and diversity.

The material covered in the present book is subdivided into five parts with twenty-two contributions in total. The logic behind these five parts is the following. Each contribution is based on a sound survey of the major events and developments that determined the history of Christian worship, which is the major focus of Part I. The four constitutive dimensions of which the liturgy consists (Eucharist, sacraments, hours, year) are presented in a systematic fashion in Part II. In addition, it is shown how these four axes and the ethos around them have always been embodied in artistic forms, auditive as well as visual and tactile, and in buildings, which explains the central attention for the connection between art and liturgy in Part III. In and through these multiple shapes and forms and celebrations, the liturgy establishes an encompassing reality which in many and diverse ways impacts people’s lives and personal identities, their communities and self-perceptions, and the role Christians (want to) play in the world and in society at large. Therefore, the multiple relations between the liturgy and the life of the churches form the subject of Part IV. This encompassing liturgical reality requires due study and understanding, not only through the texts liturgical traditions have yielded or through the appearance of Christian rituals and prayer services but also theologically. Part V closes this volume with a threefold focus on text, ritual, and theology.