The term "modernism" as applied to church history is relatively new, being used to describe the application of higher criticism, scientific discovery, and contemporary culture to the Bible, and the consequent alterations of Christian faith and doctrine in terms of this.
The fact of modernism, however, is as old as the church, and it was present in Judaism, before that in various movements, and in men like Philo. The science and culture of the times have constantly been used to try to revise and remake Christianity. In movements like Gnosticism it was an effort to convert Christianity into another religion. In other efforts, it was an endeavor to amend and impose the Faith by the use of current and prevalent thinking. The converts in the early church were formerly pagans, and they brought their mindset with them, Greco-Roman and other ideas. Neo-Platonism very early infected the church early in A. D. 390 extensively, so that men like Augustine, who took a dim view of the historicity of the Genesis creation account, were, like other church fathers of their day, modernists after a fashion. Some, like Augustine, outgrew and renounced many of their pagan views, while others retained them to their end.
It is thus dangerous and foolish to reverence the church fathers uncritically. Many were painfully in error; others transcended their severe limitations to put us in their debt.
In all sections of Christendom, every era has had its modernisms. Thus, Eastern Orthodoxy is deeply saturated with various forms of Platonism and became in many leaders an alien faith. Rome's main dereliction is also Greek, i.e., Aristotle. Protestantism very early picked up the Enlightenment reverence for rationalism. Thus, the modernism of fundamentalistic churches is their rationalistic apologetics. (Rationalism sees the priority of understanding in reason; this does not mean that anti-rationalists affirm irrationalism; rather, they insist on God's priority and the primacy of his inscripturated word.)
For examples of modernism in the church fathers, one can begin with St. Irenaeus (d. c. A. D. 202), a very able man. In his Proof of the Apostolic Preaching, he held, for example, that charity supersedes the law. He also said that the Spirit supersedes the law and also that the Spirit delivers men from the oldness of the letter of the law. We are thus beyond the law and have no need of it (Joseph P. Smith, S. J. translation: St. Irenaeus, Proof of the Apostolic Preaching, pp. 101-106. New York, N. Y.: Newman Press, 1952).
St. Gregory of Nyssa (c. A. D. 335-c. 395) was a brilliant theologian, as was his brother, St. Basil, but ability is not necessarily faithfulness to Scripture! His subtle thinking on the doctrine of the Trinity shows the Greek mind at its subtle best; but, in the practicality of interpreting the Bible, he was painfully, embarrassingly, bad. Take, for example, his work, The Life of Moses, an attempt to make the Bible readable and understandable to Greeks, especially educated Alexandrian Greeks. Writing early in A. D. 390, Gregory saw the five books of Moses as symbolic, as allegory, not as history. He held, "The narrative is to be understood according to its real intention," and his purpose was to "lay bare the hidden meaning of the history." The actual meaning was irrelevant. The "true" meaning is occult doctrine. "We are in some manner our own parents, giving birth to ourselves by our own free choice in accordance with whatever we wish to be, whether male or female, molding ourselves to the teaching of virtue or vice."
For Gregory, everything in Moses (and elsewhere) is symbolic. Thus, "The ark, constructed out of various boards, would be education in the various disciplines, which holds what it carries above the waves of life" (Abraham J. Malherbe and Everett Ferguson, translators: Gregory of Nyssa, The Life of Moses, pp. 55f. New York, N. Y.: Paulist Press, 1978). Who and what guides us? According to Gregory of Nyssa, "all the movements of our soul are shepherded like sheep, by the will of guiding reason" (ibid., p. 59). Good Platonism, that!
According to Gregory of Nyssa, there will in the end be universal salvation. He "saw" Moses as clearly teaching this (but you and I have minds too darkened to see it). Hell "will not be eternal" because Moses' outstretched hands represent "the healing of pain and the deliverance from punishment" (ibid., p. 18). Gregory was not alone in this opinion.
Naturally, for Gregory of Nyssa the dietary laws could not be about anything so crass as food! They had a higher meaning. So too did Mt. Sinai; climbing it was the ascent to God: "The majority of people scarcely reach its base" (ibid., p. 93).
Clearly, nothing in all this is recognizable as Biblical. Gregory and others like him excelled, however, in developing a rationale for the church, its rites, and its offices, so that the power of the church grew more rapidly than did its understanding.
Am I rejecting patristic literature? Far from it: I respect and use what is good in it, whatever is Biblical. I do very emphatically reject the ungodly reverence for and kow-towing to the authority of idealized church fathers. It is unrealistic and foolish.
We cannot combat the errors of our time if we cannot recognize kindred errors in the past. Ancient modernisms are no more to be accepted than contemporary ones. In every era, the modernisms of the day have reshaped men's views of the Bible when in fact the Bible requires us to reshape our world, our times, and ourselves in terms of the word of God.
Whatever one says about Gregory of Nyssa, Origen, and others like them, our attitude towards those who give priority to them over the word of God must elicit our clearer condemnation. These ancients were often in error, sometimes in the truth, but they did represent sometimes feeble, sometimes very real, steps in the growth of the Faith. This was true even of Origen, whom I particularly dislike. The important question is this: Is the cause of Christ advanced in and through us?