There is an emerging literature on Pentecostal ecclesiology and some disagreement as to how that ecclesiology should be done. It is still the case that idealised biblical and theological ecclesiologies predominate, but Davidsson's work is a superb example of a concrete method that takes history and social context seriously. From this perspective, ecclesiology begins from below, describing and analysing what the church actually is and how it understands itself, before attending to what it is supposed to be (p.11). For those interested in doing Pentecostal (or any) ecclesiology, Davidsson's final chapter includes an insightful evaluation of alternative methods used by seminal Pentecostal scholars, and whether or not one agrees with his conclusions (and I generally do), his argument deserves to be taken seriously.
The concrete ecclesiology that is the focus of Davidsson's analysis is that of Lewi Pethrus (1884-1974). A Swedish pastor ordained as a Baptist minister, Pethrus experienced the Pentecostal revivals that swept the world at the turn of the 20th century and was Baptised in the Spirit in 2007. Pethrus remained within the Baptist Union until 1913, when he and the church he led were excommunicated over concerns about Pentecostal theology and practices (Spirit baptism and an "open" interpretation of communion (p.63)). Thereafter, the Filadelphia Church of Stockholm grew to become one of the largest Pentecostal assemblies in Europe, and Pethrus the de facto leader of the Swedish Pentecostal Movement (SPM). His ecclesiology – which developed over decades and is accessed through his written publications, sermons, and the practice of his ministry – thus influenced churches throughout Sweden and beyond. Because most of the writing by and about Pethrus is in Swedish, his story is largely unknown in the English-speaking world, a situation that is thankfully rectified by Davidsson, a dual language scholar.
I will leave it to Davidsson to tell the colourful story of Pethrus and the churches he influenced. His account and analysis is both sympathetic and critical. Davidsson, who writes as an insider to the SPM, does an excellent job at setting Pethrus' ecclesiology and church practices within their ecclesial and social context, before bringing critical judgement. What stands out most is the ways in Pethrus' ecclesiology develops and morphs as the tumultuous decades of the 20th century unfold.
Consider, for example, his attitude to ecumenism. While Pethrus' earliest experiences of the Pentecostal revival had church unity at its heart, his excommunication entrenched his sense that organisational unity should be rejected for the sake of the "far superior" and inward unity of the Spirit (p.134). His suspicion of institutional unity extended to the ecumenical efforts of World Council of Churches (WCC), and in the 1920s Pethrus espoused a fascinating conspiracy theory that interpreted the Roman Catholic Church's absence from the WCC as a strategy intended to encourage other denominations to unite, after which Rome would re-exert its authority (p.93). In the early 1960s he likened the aims of the WCC to the totalitarian vision of Communism and Nazism (p.181). Even so, as the charismatic movement took hold later in that decade, Pethrus came to recognise the work of the Spirit amongst mainline denominations, including charismatic Catholics, and to appreciate the interactions of David du Plessis with the WCC. Late in his life and ministry he publicly supported the ecumenical dialogue between the Roman Catholic Church and global Pentecostalism (p.171-187). It would be easy enough to critique the inconsistency in Pethrus' ecumenical thinking and actions, but Davidsson looks deeper and identifies a consistent core. For Davidsson, Pethrus' openness to the shared experience of the Spirit was the essential core to his theology in general and ecclesiology in particular. And this underlying and consistent spirituality enabled Pethrus to respond to changes in his social context in creative and sometimes surprising (and seemingly contradictory) ways.
Davidsson argues that Pethrus' understanding of the Pentecostal movement itself reveals a similar spiritual consistency and contextual flexibility. Although pioneering one of the first and most influential Pentecostal mega-churches in Europe, Pethrus had no interest in establishing Pentecostal distinctives, creeds, or seminaries, and lamented the fact that Pentecostalism had become a movement for Pentecostal's (p.214). He understood Pentecostal renewal as a spiritual revival of the church, not the formation a new denomination. He thus sharply criticised the institutionalisation of Pentecostalism, and he publicly rejected the denominational Pentecostalism that arose in North America and other places. Under Pethrus, the SPM understood itself "is a spiritual fellowship of independent local churches," but as Davidsson makes clear, in reality it functioned in much the same way as any other denomination (p.1. & 201-206). Indeed, Pethrus' rejection of institutionalisation was not a denial of the importance of church structure and hierarchy. He insisted, for example, that the New Testament's ideal pattern was for one church in each city, and then went on to develop a one city — one (mega-) church model, in which the mega church functioned as a central headquarters, managing financial, ministerial, and administrative responsibilities of outpost assemblies (p.130). Davidsson notes the irony of Pethrus' insistence on the independence of the local church, alongside his assumption that other Pentecostal churches in Stockholm should recognise his authority. He was the great proponent of the independent church model, however he often "acted as a bishop" (p.106).
Pethrus' ecclesiology is fluid. But Davidsson argues that it would be a mistake to judge it as unsophisticated and inconsistent, just as it would to dismiss the possibility of a global Pentecostal ecclesiology in the face of its bewildering diversity. And thus Davidsson's constructive contribution to the wider exploration of Pentecostal ecclesiology is his identification of a transdenominational Pentecostal ecclesiology (the subtitle of his book); that Pentecostal spirituality enables a creative tension between the unchanging innermost core of Christianity – religious affections that emphasise loving Christ and loving neighbour – and shifting ecclesial contexts. He goes on to argue that "research into a global Pentecostal ecclesiology should follow the same inner logic as manifested in Pethrus ecclesiology, namely that the value Pentecostals place on a particular form of spirituality gives the movement its essential unity, whereas formative contexts provide its concrete diversity" (p.225). And because Pentecostal identity is oriented to ecumenical revival, it is an inclusive ecclesiology, open wide for anyone who loves Christ and neighbour in a Pentecostal way (p.218).
It is somewhat ironic that Davidsson's thoroughly concrete ecclesiological method leads him to what might be judged as an idealised conclusion. Indeed, it is hard to identify the practical outcomes of his transdenominational ecclesiology. To say that a core spirituality provides us a way of understanding ecclesiological diversity and fluidity does little to help make judgements about the ecclesiological structures that emerge. Having said that, it is when this idealised conclusion is kept in tension with the concrete story that the transdenominational method gains traction. Looking at the SPM from an Australian perspective, I note that the one city one mega church (multiple outpost) model prefigures the multi-campus mega-church model that has arisen recently in Australia, and I wonder whether comparative analysis of these stories might yield further insight about the advantages and dangers that attend to the power leaders have in multi-all campus (or outpost) mega-churches? And this comparison invites analysis that takes into account the idealised biblical and theological ecclesiologies of Wolfgang Vondey, Miroslav Volf, Amos Yong, Frank Macchia and others that are, perhaps, dismissed prematurely by Davidsson – and certainly by me in my various ecclesiological investigations in years gone by.
In any case, Davidsson's ecclesiology deserves to be given serious attention in the Pentecostal Academy.
 Shane Clifton is Professor of Theology, Alphacrucis College.
 My argument for a concrete ecclesiology is set out in Shane Clifton, Pentecostal Churches in Transition: Analysing the Developing Ecclesiology of the Assemblies of God in Australia (Leiden, The Netherlands: Brill, 2009).
 Shane Clifton, "Australian Pentecostalism: Origins, Developments, and Trends," in Global Renewal Christianity: Asia and Oceania Spirit-Empowered Movements: Past, Present, and Future, ed. Amos Yong and Vinson Synan (Lake Mary, Florida: Charisma House, 2016).