To look back to the early Church as a theologian and historian, and ask questions about her unity, is to enter on a long tradition, which goes back at least to the Reformation, if not to the Great Schism of 1054 itself. Once the Church had split, the various separated Christians looked back to justify their position in that tragedy. They scoured the early sources for evidence for and against episcopacy, papacy, authority confided to tradition or to Scripture alone: they questioned the form in which these early sources have come down to us - the sixteenth century saw reserves of scholarly genius poured into the problem, for instance, of the genuineness of the Ignatian correspondence, and what fired all that, apart from scholarly curiosity, was the burning question of the authenticity of episcopal authority on which Ignatius speaks so decisively. Out of that the critical discipline of patristics emerged. It was, in fact, rather later that the fourth century became the focus of the debate about the unity, authority, and identity of the Church - Newman obviously springs to mind and his Arians of the Fourth Century (London, 1833) and his Essay on the Development of Doctrine (London, 1845). Later on, the fourth century attracted the attention of scholars such as Professor H. M. Gwatkin and his Studies in Arianism (Cambridge, 1882), and Professor S. L. Greenslade and his Schism in the Early Church (London, 1953), and in quite modern times Arianism, in particular, has remained a mirror in which scholars have seen reflected the problems of the modern Church (a good example is the third part of Rowan Williams’s Arius: Heresy and Tradition [London, 1987], though there are plenty of others). Continental scholars such as Adolf von Harnack also studied the past, informed by theological perspectives derived from the present; in a different and striking way Erik Peterson turned to the fourth century to find the roots of an ideology of unity that was fuelling the murderous policies of Nazism. In all these cases the fourth century seemed to be a test case ‒ for questions of modern ecclesiology: Rome defended by development in the case of Newman, the justification for the ecumenical movement in the case of Greenslade.
Law and the Protestant Reformation
