In ‘Philology and the Incarnation’ — his own version of Sir Thomas Browne’s Religio Medici — Barfield explains how his own thinking on the evolution of consciousness, in particular his study of language as a record of that evolution, eventually required his acceptance of the teachings of Christianity. The raised-as-an-agnostic Barfield had no Damascus, no moment of conversion. The facts of the evolution of consciousness logically required him to become a Christian.

It is possible—I know because it happened in my case—for a man to have been brought up in the belief, and to have taken it for granted, that the account given in the Gospels of the birth and the resurrection of Christ is a noble fairy story with no more claim to historical accuracy than any other myth; and it is possible for such a man, after studying in depth the history of the literature and tradition that has grown up around it and to accept (if you like, to be obliged to accept) the record as a historical fact, not because of the authority of the Church, nor by any process of ratiocination such as C. S. Lewis has recorded in his own case, but rather because it fitted so inevitably with the other facts as he had already found them. Rather because he felt, in the utmost humility, that if he had never heard of it through the Scriptures, he would have been obliged to try his best to invent something like it as a hypothesis to save the appearances.
(Rediscovery of Meaning 350)

Throughout his books he discusses the pivotal role of Christ in the development of human consciousness.

For Barfield, Christ is, first and foremost, “the cosmic wisdom on its way from original to final participation.” “In Christ . . . we participate finally the Spirit we once participated originally” (Saving the Appearances 219) Thanks to Christ, Barfield would write in ‘From East to West’, “the human Ego, the true Self, of man descended from the purely spiritual heights, where it hitherto dwelt, to the earth. Had Christ not come to earth, individual human beings would never have been able to utter the word ‘I’ at all” (Romanticism Comes of Age 56).

Barfield’s Christianity was through and through informed by Anthroposophy and at times becomes extremely esoteric. Consider, for example, the following passage, in which the Meggid explains Christ’s past lives:

The soul of Jesus of Bethlehem was indeed the fruit of many previous lives, and there is allusion to this in the genealogy which precedes the account of his birth, and which is traced back only to Abraham-that is, approximately to the stage of emergence . . . when individuality had for the first time been recognizably attained by the human spirit. . . . The physical pedigree of Jesus of Nazareth is drawn from David through another son, the priest Nathan. But the provenance of the soul that was born in this Jesus is a deeper mystery. It had known no previous lives on earth. It was indeed an Eden-soul, unfallen, and given intact from the Father Spirit to be the persisting link between the old state of the human spirit and the new. . .

Think only of those two souls-through what millennia prepared for that moment!-uniting to form, as it were, a chalice in which the Timeless, in which the Timeless that both dies and dies not, could indeed enter into time-as it did when the man Jesus was baptized by John in the River Jordan, and the uncreated light, the untransformed transforming, entered his consciousness and became also the Christ of history.
(Unancestral Voice 150)

Barfield strives to remind us how extraordinary the Christian myth is, and he endeavors to reiterate it with fresh wonder:

In the heart of that nation [Israel], whose whole impulse it had been to eliminate original participation [a process Barfield details in Saving the Appearances], a man was born who simultaneously identified himself with, and carefully distinguished himself from, the Creator of the world—whom he called the Father. On the one hand: “I am not alone, but I and the Father that sent me,” etc. On the other: “I and the Father are one,” etc. In one man the inwardness of the Divine Name had been fully realized; the final participation, whereby man’s creator speaks from within man himself, had been accomplished. The Word had been made flesh.
(Saving the Appearances 199)

Christianity was thus a response to a felt need:

the incarnation of Christ in a human body, and subsequently in the “aura” of the earth, was the solution in fact of that divorce between a subjective and an objective world which had only recently arisen in human experience. . . . In the last great period of civilisation a question stood before the whole earth—the question whether it should henceforth have a meaning. And the question was answered by the deed of God, who brought meaning to the earth from the Sun.
(Romanticism Comes of Age 123)

“Christianity, in its abstract purity,” he would write conclusively, “became the exoteric expression of the esoteric doctrines of the poetry and wisdom of antiquity”, but he had already expressed the same idea thirty years before in History in English Words.

In Palestine, Jesus of Nazareth lived and taught and died. As the years passed by, an increasing number of sages and religious teachers began to agree among themselves that recently something had actually occurred which had before only been talked about or erroneously believed to have occurred. Certain of the Jews, for instance, admitted that their Messiah had come and gone. Egyptians and followers of the Egyptian cults were persuaded that a real Horus had been born of a virgin, and had risen again as an Osiris. Some of the more forward-looking among those who had been initiated into the Mysteries felt that what had so often been enacted dramatically within the sacred precincts had now taken place in a peculiar way on the great stage of the world, this time not for a few, but for all to see. A God had himself died in order to rise again to eternal life. Thus, those who had not been initiated—the poorer classes, most of the women, and the slaves—had a joyous feeling that at last the Mysteries had been revealed, that “many things which were hid had been made plain.” And some students of Platonic philosophy could admit that this might be true, that henceforth those who could not rise to the contemplation of the eternal in Nature might yet win immortality by contemplating the life and death of Jesus.
(History in English Words)

Whereas some critics of Christianity—Nietzsche for example—have condemned it for usurping and demeaning Greek thought, Barfield finds in Christ an incarnate fulfillment of Greek wishful thinking:

For Christ . . . had first taught in a new and simpler way, and had then himself demonstrated, a truth which nearly every one of the Greek philosophers, including Aristotle, had been trying to say all their lives—that, in order to achieve immortality, it is necessary to “die” to this world of the senses and the appetites, and that he who thus “dies” is already living in eternity during his bodily life and will continue to do so after his bodily death. “Whosoever shall lose his life shall find it.”
(History in English Words)

Finally, the most distinctive feature of Christianity, as Barfield emphasizes on a number of occasions, remains its historicity:

What is peculiar in Christianity is the nexus . . . between the Second Person of the Trinity [Christ, the Logos] and a certain historical event in time. For the Christian, accordingly, religion can never be simply the direct relation between his individual soul and the eternal Trinity. As long as we ourselves are occupying a standpoint in time, so long, interposed between the First and Third Persons, all history, in a manner lies.
(Saving the Appearances 195)

Yet surely the thing that more than all else distinguishes Christianity from other religions is that it does take serious account of time—and… not just short periods, not just the time of an individual biography. It accepts historical time as a reality, and a reality relevant to its own truth.
(Unancestral Voice 118)

Only Christianity, Barfield would argue, makes possible the concept of the evolution of consciousness.