Doctrines are the authoritative teachings of the Church, yet the modern church is hampered by its inability to speak authoritatively even to its own members on matters of doctrine. One reason is that doctrines are widely perceived as archaic and fixed formulations with little significance for the present day. True doctrines, in fact, are constantly developing as the Church moves towards eschatological fulfillment. Yet for doctrines to develop properly there needs to be a proper ecclesiology. The Church is not an entity that God brought into being to return creation to its original purpose after the Fall; rather, the Church is prior to creation, chosen in Christ before the creation of the world (Eph. 1.4). It is a divine-humanity, ontologically linked to Christ the Head. It is the living Body of Christ, the totus Christus.Within the continuing life of prayer and worship, the Church's doctrines are re-enacted, renewed and developed. These acts constitute the ecclesial experience or the living tradition. The living tradition is the transmission and development of the gospel of Jesus Christ in the on-going practices of the Church through the power of the Holy Spirit. The coming of the Spirit upon the Church at Pentecost is not just to enable the Church to preach the gospel but to constitute the Church as part of the gospel itself. That is to say, the gospel story includes the story of the Spirit in the Church. The third person of the Godhead is revealed as such in his special relation to the Church. The Church, therefore, could be called the 'polity of the Spirit', that is, the public square in which the Spirit is especially at work to bring God's ultimate purpose to fulfillment. There is, therefore, no separation between ecclesiology and pneumatology. They are necessary for maintaining the living tradition and ensuring the healthy development of doctrine until the Church attains unity of the faith. Pentecostals who see the Pentecost event as the distinctive mark of their identity have a special role to play: by becoming more truly catholic in their ecclesiology, they become more truly Pentecostal. This accords well with their early ecumenical instinct. Doctrines are the authoritative teachings of the Church, yet the modern church is hampered by its inability to speak authoritatively even to its own members on matters of doctrine. One reason is that doctrines are widely perceived as archaic and fixed formulations with little significance for the present day. True doctrines, in fact, are constantly developing as the Church moves towards eschatological fulfillment. Yet for doctrines to develop properly there needs to be a proper ecclesiology. The Church is not an entity that God brought into being to return creation to its original purpose after the Fall; rather, the Church is prior to creation, chosen in Christ before the creation of the world (Eph. 1.4). It is a divine-humanity, ontologically linked to Christ the Head. It is the living Body of Christ, the totus Christus.Within the continuing life of prayer and worship, the Church's doctrines are re-enacted, renewed and developed. These acts constitute the ecclesial experience or the living tradition. The living tradition is the transmission and development of the gospel of Jesus Christ in the on-going practices of the Church through the power of the Holy Spirit. The coming of the Spirit upon the Church at Pentecost is not just to enable the Church to preach the gospel but to constitute the Church as part of the gospel itself. That is to say, the gospel story includes the story of the Spirit in the Church. The third person of the Godhead is revealed as such in his special relation to the Church. The Church, therefore, could be called the 'polity of the Spirit', that is, the public square in which the Spirit is especially at work to bring God's ultimate purpose to fulfillment. There is, therefore, no separation between ecclesiology and pneumatology. They are necessary for maintaining the living tradition and ensuring the healthy development of doctrine until the Church attains unity of the faith. Pentecostals who see the Pentecost event as the distinctive mark of their identity have a special role to play: by becoming more truly catholic in their ecclesiology, they become more truly Pentecostal. This accords well with their early ecumenical instinct.