Since I'm swamped with reading between now and the end of the month, I thought I would use these to post the results of some of my research. Over the next couple of days, I will post a concise summary, in my own words, of the definitive historical work of the Venerable John Henry Newman, An Essay on the Development of Christian Doctrine. I will do this in several posts, which I will post in such a way that they can be read 'downward' from the top. While perhaps a bit lacking in creativity on my part, I hope those who have neither the time nor the background to tackle Newman's work directly might benefit by a concise summation of his arguments, which, IMHO, provide an acute and unsurpassed grasp of the history of Christian doctrine.
Christianity cannot be treated as a matter of mere private opinion, but rather as an objective fact of history and a matter of public importance. When assessing the history of the Christian religion, we must also take as our starting point an assumption of its historical continuity, i.e., that the Christianity which exists today is, more or less, the same Christianity which existed in the day of the apostles; and we must lay the burden of proof on those who would insist otherwise. If an examination of this history shows us anything, it shows us that "the Christianity of history is not Protestantism." In fact, one can even say that "to be deep in history is to cease to be a Protestant."
While some theologians claim that we must accept as orthodoxy only what has been believed 'by all men at all times and in all places,' we respond that this naive theory fails, because it cannot admit one to accept desirable teachings of the Fathers (such as the Trinity) without equally admitting undesirable Roman teachings (such as the primacy of the Roman See). In fact, this theory 'cannot hold firm the doctrines of Canterbury without admitting those of Rome.'
The theory of this essay is that the magnificent doctrines of our faith have developed only over the course of time, in which they have only gradually been comprehended and explicitly defined by the Church, just as all ideas only reach their full elucidation in the human mind when they are given appropriate time for germination.