Such a theory was not entirely novel; Irenaeus, for instance, urged it in an unsuccessful attempt to settle the paschal controversy. But as local customs became fixed the theory was more and more invoked, and it finally became a settled principle throughout Christendom. The fourth century was here the definite turning point; when the ecumenical councils met, they made no attempt to legislate in full details for the whole church. So when the compiler of the Apostolic Constitutions _ca._ 375 revived the Church Order formula that made all the apostles legislate minutely, we may presume that he was consciously adopting a style that was already somewhat obsolescent; Christians by now were becoming aware that collective apostolic authority could not be claimed for so wide an extent of regulations. And this consciousness brought with it the eventual end of the Church Orders; they were replaced by explicitly local collections of canons and by liturgical service books. Yet in many parts of the church the old Church Orders retained their authority, and they were incorporated into the manuals of canon law. The following are the chief Church Orders: THE DIDACHE As this work is familiar to everyone its contents need not be described. Most scholars date it in the early years of the second century, but the possibility that its compiler used the Epistle of Barnabas as a source cannot be wholly disregarded.[21] Barnabas is usually dated about 131, with a possibility of belonging some fifteen years earlier, so if the dependence is accepted the Didache could scarcely have originated before the second quarter of the century and may even be somewhat later. The influence of the Didache in the early church was wide and it was held in high honour. It was incorporated into the Didascalia, the Apostolic Church Order and the Apostolic Constitutions. So eminent and orthodox a saint as Athanasius speaks of it as a book very profitable for neophytes “who wish for instruction in the word of godliness”,[22] and he cites it as an authority more than once, even though he—very properly—refuses to recognize it as a canonical New Testament writing.[23] There consequently can be no reasonable doubt that the Didache originated in the broad stream of orthodox Christian tradition, not in some obscure heretical sect. Much the most convenient edition of the Greek text is that edited by Dr Hans Lietzmann in his _Kleine Texte_ series;[24] it contains an excellent critical apparatus and is very inexpensive. There are many accessible English translations. THE APOSTOLIC TRADITION This work of Hippolytus, the subject of the present volume, is named here to preserve the chronological sequence. In its Coptic and other versions it was formerly known as the Egyptian Church Order. THE DIDASCALIA