The most elaborate and systematic exposition of this theory is exhibited in the "Essay on the Development of Christian Doctrine, by John Henry Newman;" an Essay primarily directed to the discussion of the points of difference between the Popish and the Protestant Churches, but which will be found to have an important bearing, also, on some doctrines which are common to both, and especially on the fundamental articles of Natural Religion itself.

It is thus stated by Mr. Newman:[91] "That the increase and expansion of the Christian Creed and Ritual, and the variations which have attended the process in the case of individual writers and churches, are the necessary attendants on any philosophy or polity which takes possession of the intellect and heart, and has had any wide or extended dominion; that, from the nature of the human mind, time is necessary for the full comprehension and perfection of great ideas; and that the highest and most wonderful truths, though communicated to the world once for all by inspired teachers, could not be comprehended all at once by the recipients, but, as received and transmitted by minds not inspired, and through media which were human, have required only the longer time and deeper thought for their full elucidation. This may be called the Theory of Developments."

It is further illustrated as follows: "It is sometimes said that the stream is clearest near the spring. Whatever use may fairly be made of this image, it does not apply to the history of a philosophy or sect, which, on the contrary, is more equable, and purer, and stronger, when its bed has become deep, and broad, and full. It necessarily rises out of an existing state of things, and, for a time, savors of the soil. Its vital element needs disengaging from what is foreign and temporary, and is employed in efforts after freedom, more vigorous and hopeful as its years increase. Its beginnings are no measures of its capabilities, nor of its scope. At first, no one knows what it is, or what it is worth. It remains, perhaps, for a time, quiescent; it tries, as it were, its limbs, and proves the ground under it, and feels its way. From time to time it makes essays which fail, and are, in consequence, abandoned. It seems in suspense which way to go; it wavers, and, at length, strikes out in one definite direction. In time it enters upon strange territory; points of controversy alter their bearing; parties rise and fall about it; dangers and hopes appear in new relations, and old principles reappear under new forms; it changes with them, in order to remain the same. In a higher world it is otherwise; but here below to live is to change, and to be perfect is to have changed often."[92]

In answer to the objection, "that inspired documents, such as the Holy Scriptures, at once determine the doctrines which we should believe," it is replied, "that they were intended to create an idea, and that idea is not in the sacred text, but in the mind of the reader; and the question is, whether that idea is communicated to him, in its completeness and minute accuracy, on its first apprehension, or expands in his heart and intellect, and comes to perfection in the course of time. Nor could it be maintained without extravagance that the letter of the New Testament, or of any assignable number of books, comprises a delineation of all possible forms which a Divine message will assume when submitted to a multitude of minds."[93]

What relation, it may be asked, can this theory respecting the development of revealed or Christian truth bear to the question of the being and perfections of God? We answer, that it is founded on a general philosophical principle which may affect the truths of natural as well as those of revealed Religion; and that it is applied in such a way as to show that, as it has already led to the worship of angels and saints, so it may hereafter issue in the deification of Nature, which is Pantheism, or in the separate worship of its component parts, which is Polytheism; and, in either case, the personality and supremacy of the one only, the living and the true God, would be effectually superseded, if not explicitly denied.

But, is there any real danger of such a disastrous consummation? We answer, that the mere coexistence of the theory of Ecclesiastical Development with the infidel speculations on the doctrine of Human Progress is of itself an ominous symptom; and, further, that the mutual interchange of complimentary acknowledgments between the Infidel and Popish parties is another, especially when both are found to coincide in some of the main grounds of their opposition to Scripture as the supreme rule of faith, and when the homage which the advocates of Development render to the theory of progress is responded to by glowing eulogiums from the infidel camp on the genius of Catholicism as the masterpiece of human policy. But there are other grounds of apprehension, arising more directly out of the very nature of the theory of Development itself.

That theory has been described by Dr. Brownson—himself a convert to Catholicism—as the product of "a school formed, at first, outside of the Church, but now brought within her communion," and compared, in regard to its dangerousness, with the speculations of Hermes and Lamennais.[94] And a still more competent judge—Professor Sedgwick, of Cambridge[95]—has characterized it as "a monstrous compound of Popery and Pantheism," according to which "the Catholic faith is not a religion revealed to us in the Sacred Books we call canonical, and in the works of the Fathers which are supposed to contain the oral traditions of the Apostles and their followers; but a new Pantheistic element is to be fastened on the faith of men,—a principle of Development which may overshadow both the verbum Dei scriptum and the verbum Dei non scriptum of the Romish Church, and change both the form and substance of primitive Christianity."

It is only justice to Mr. Newman to say that he appears to have been aware of this possible objection to his theory, and that he makes an attempt to obviate it. Speaking of the difficulty which the Church experienced in keeping "Paganism out of her pale," he adverts to "the hazard which attended on the development of the Catholic ritual,—such as the honors publicly assigned to saints and martyrs, the formal veneration of their relics, and the usages and observances which followed." And he asks: "What was to hinder the rise of a sort of refined Pantheism, and the overthrow of Dogmatism pari passu with the multiplication of heavenly intercessors and patrons? If what is called in reproach 'Saint-worship' resembled the Polytheism which it supplanted, or was a corruption, how did Dogmatism survive? Dogmatism is a religious profession of its own reality as contrasted with other systems; but Polytheists are liberals, and hold that one religion is as good as another. Yet the theological system was developing and strengthening, as well as the monastic rule, all the while the ritual was assimilating itself, as Protestants say, to the Paganism of former ages."[96]

It seems to be admitted in these words, that, in the past history of the Church, the development of the Catholic ritual was attended with some danger of infection from Paganism or Pantheism; and there may be equal reason to fear that, in the future history of the Church, still working on the principle of development, that danger may be very considerably aggravated by the general prevalence of theories utterly inconsistent with the faith of primitive times. What the Church has already done in the exercise of her developing power may be only a specimen of what she may hereafter accomplish. She has already developed Christianity into a system which bears a striking resemblance to Polytheism; she may yet develop it more fully, so as to bring it into accordance with philosophical Pantheism; or, retaining both forms,—for they are not necessarily exclusive of each other,—she may use the first in dealing with the ignorant, and reserve the second as a sort of esoteric doctrine for minds of higher culture. Nor let it be said that we are either unjust or uncharitable towards the Romish Church, in suggesting the possibility of some such development; for what she has already done, and what she still claims the power of doing, afford very sufficient ground for our remarks. When Dr. Conyers Middleton published his celebrated "Letter from Rome," showing an exact conformity between Popery and Paganism, and that "the religion of the present Romans is derived from that of their Heathen ancestors," many liberal Catholics resented the imputation as an insult to their faith; but now Mr. Newman not only admits the fact that the Church did assimilate its ritual to the Paganism of former ages, but vindicates her right to do so, and ascribes to her a power of assimilation to which it seems impossible to assign any limits. "There is, in truth," says this writer, "a certain virtue or grace in the Gospel, which changes the quality of doctrines, opinions, usages, actions, and personal characters, which become incorporated with it, and makes them right and acceptable to its Divine Author, when before they were either contrary to truth, or, at best, but shadows of it."—"Confiding, then, in the power of Christianity to resist the infection of evil, and to transmute the very instruments and appendages of demon worship to an Evangelical use, ... the rulers of the Church from early times were prepared, should the occasion arise, to adopt, or imitate, or sanction the existing rites and customs of the populace, as well as the philosophy of the educated class."—"The Church can extract good from evil, or, at least, gets no harm from it. She inherits the promise made to the disciples, that they should take up serpents, and, if they drank any deadly thing, it should not hurt them."—"It has borne, and can bear, principles or doctrines which, in other systems of religion, quickly degenerate into fanaticism or infidelity." This marvellous power of assimilation, which made "those observances pious in Christianity" that were "superstitions in Paganism," advanced, rapidly in its work, and successively introduced the deification of man, the cultus of angels and saints, and the beatification of Mary as Queen of heaven and earth. The sanctification, or rather the deification of the nature of Man, is one of these developments. Christ "is in them, because He is in human nature; and He communicates to them that nature, deified by becoming His, that it may deify them." The worship of saints is another of these developments: "Those who are known to be God's adopted sons in Christ are fit objects of worship on account of Him who is in them.... Worship is the necessary correlative of glory; and, in the same sense in which created nature can share in the Creator's incommunicable glory, do they also share in that worship which is His property alone." But a "new sphere" was yet to be discovered in the realms of light, to which the Church had not yet assigned its inhabitant. "There was 'a wonder in heaven;' a throne was seen, far above all created powers, mediatorial, intercessory; a title archetypal; a crown bright as the morning star; a glory issuing from the Eternal Throne; robes pure as the heavens; and a sceptre over all. And who was the predestined heir of that Majesty? Who was that Wisdom, and what was her name?—'the Mother of fair love, and fear, and holy hope,' exalted like a palm-tree in Engaddi and a rose-plant in Jericho, created from the beginning before the world in God's counsels, and 'in Jerusalem was her power.' The vision is found in the Apocalypse, a Woman clothed with the Sun, and the Moon under her feet, and upon her head a crown of twelve stars." The Deification of Mary is decreed. The doctrine of her Immaculate Conception is a further development at the present moment, and who can tell what other developments may be in store for the future?

We advert to this form of the theory only in so far as it stands related to our great theme,—the existence, perfections, and prerogatives of the one only, the living and the true God; and it can scarcely be questioned, we think, that it has already introduced doctrines and practices into the Church which have a manifest tendency to obscure the lustre and impair the evidence of some of the most fundamental articles of Natural Religion. Let it still advance in the same direction, and who shall assure us that it may not develop into still grosser idolatry, or even into Pantheism? Why should it not develop, for example, into Sun worship? "On the new system," says Professor Butler, "a modern growth of Christian Guebres might make out no feeble case; the public religious recognition of this great visible type of the True Light is but a fair development of 'the typical principle;' the justifiable imitation of the guilt of heathens in its adoration is but an instance of the transforming powers of 'the sacramental principle;' while it requires but the most moderate use of the great instrument of orthodoxy, 'mystical interpretation,' to find the duty hinted (clearly enough for watchful faith, though obscurely to the blinded or undevout) in those passages that speak of a 'tabernacle for the Sun,' or Deity itself being 'a Sun,' or the rising of 'the Sun of righteousness.'... Indeed, the whole body of the righteous are promised to 'shine as the Sun' in the heavenly kingdom,—an expression which, though it appear superficially to refer to a period not yet arrived, the Church has correctively developed into an assurance of their present beatification, and consequent right to worship; while it must be at once manifest that, if any representative emblem of the Deity may demand religious prostration in our Churches, the analogous emblem of the 'deified,' in the great temple of the Material Universe, may fairly expect a participation in that honor. It is true there is an express command, 'Take heed lest, when thou seest the Sun, ... thou shouldst be driven to worship them;' but so there is a command, at least as distinct and imperative, against the worship of Images, which, Mr. Newman instructs us, has been repealed under the Gospel, and was never more than a mere Judaic prohibition, 'intended for mere temporary observance in the letter.'"[97]