But _does_ the development of doctrine, in the sense contended for by the author of the celebrated Essay, mean making actual additions to the faith once for all delivered, as distinct from arriving at a better comprehension of the contents and logical consequences of the original deposit? This question must be answered in the affirmative, for various reasons. The whole purpose of the Essay, and the actual expressions used in it, require this meaning; and that this is the obvious meaning has been assumed by Roman Catholic as well as Protestant critics, and (so far as the present writer is aware) this interpretation has never been resented as illegitimate by the author. The whole argument is admittedly "an hypothesis to account for a difficulty," "an expedient to enable us to solve what has now become a necessary and an anxious problem" (pp. 27, 28), viz. the enormous difference between the sum total of Roman Catholic doctrines and those which can be found in the Christian documents of the first two or three centuries. The Essay is believed by its author to furnish "a solution of such a number of the reputed corruptions of Rome as might form a fair ground for trusting her where the investigation had not been pursued" (p. 29). And that the faith once for all delivered is regarded as in need of supplements and additions seems to be implied in such language as the following: "In whatever sense the need and its supply are a proof of design in the visible creation, in the same do _the gaps_, if the word may be used, _which occur in the structure of the original creed of the Church_, make it probable that those developments, which grow out of the truths which lie around them, were intended to complete it" (pp. 101, 102). It is the business of succeeding ages of the Church to "keep what was exact, and _supply what was deficient_" (p. 354).
The author of the _Essay on the Development of Christian Doctrine_ states in another of his works that when he was admitted to the Church of Rome he embraced volumes containing the writings of the Christian Fathers, crying out that now they were really his own. The action and exclamation were thoroughly inconsistent with the position maintained throughout the Essay, and since then adopted by numbers of Roman controversialists. He ought rather to have cleared his shelves of the works of the Fathers, and to have consigned them to the lumber-room, with the remark, "Now I need never look at you any more." As Bishop Cornelius Mussus (Musso) said long ago, "For my part, to speak quite frankly, I would give more credence to a single Pope than to a thousand Augustines, Jeromes, and Gregorys" (_In Epist. ad Rom._ xiv., p. 606, Venet., 1588, quoted in Hardwick's edition of Archer Butler's _Letters on Romanism_, p. 394). It is the latest and most modern works on Roman theology, especially those which expound the utterances of the most recent Popes, that deserve to be studied, if the theory of the development be correct. According to that theory, the teaching of the primitive Church was certainly immature and defective, and possibly even erroneous. In order to find out what primitive writers meant, or _ought to have meant_, we must look to the latest developments. _They_ are the criteria by which to test the teaching of the early Church; it is beginning at the wrong end to test the developments by Christian antiquity. In former times Romanists were at great pains to show that traces of their peculiar tenets could be found in the writers of the first few centuries; and in not a few cases the works of these primitive writers were interpolated, in order to make out a fair case. Criticism has exposed these forgeries, and it has been demonstrated that the early Christian teachers were ignorant of whole tracts of Roman doctrine and practice. Roman controversy has therefore entirely shifted its ground. It now freely admits that these things were unknown to Irenæus, Cyprian, Chrysostom, Athanasius, and Augustine; but for the simple reason that, when they wrote, these things had not yet been revealed. The Church was still ignorant that the Blessed Virgin was conceived without sin, was taken bodily to heaven after her death, and ought to be invoked in prayer; it was still ignorant of the doctrine of purgatory, of indulgences, and of the necessity of being in communion with the Church of Rome. It will not do to say that Christ and His Apostles planted the _germs_ of these things, and that for centuries the germs did not expand and fructify, and therefore remained unnoticed. For, first, how can there be _a germ of an historical fact_, such as the supposed removal of the Virgin's body to heaven, which is most happily named an "assumption"? Secondly, now that the fruit _has_ appeared, we ought to be able to trace it back to the germ which for so long was ignored. And thirdly, if the germs were really deposited by Christ and His Apostles, they would have developed in a _somewhat_ similar manner in all parts of Christendom. Different surroundings will account for some variety of development, but not for absolute difference in kind. The germ respecting communion with the Church of Rome, if there was one, developed in the East, where all germs were in the first instance planted, into the doctrine that no such communion was necessary.[111] Therefore, from the Roman point of view, it is necessary to maintain that the development of Christian doctrine involves, not merely the better comprehension of the contents of doctrines, and the expansion of seeds and germs of truth, but the admission of actual supplements and additions, derived from new revelations of fresh items of truth. As the Jesuit Father Harper said, in his reply to Dr. Pusey's _Eirenicon_, "Christ grew in wisdom daily. So does the Church, not in mere appearance, but of truth. Her creed, therefore, can never shrink back to the dimensions of the past, but must ever enlarge with the onward future."