Pre-existence of Christ
For who beside the Father could clearly understand the Light which was before the world, the intellectual and essential Wisdom which existed before the ages, the living Word which was in the beginning with the Father and which was God, the first and only begotten of God which was before every creature and creation visible and invisible, the commander-in-chief of the rational and immortal host of heaven, the messenger of the great counsel, the executor of the Father’s unspoken will, the creator, with the Father, of all things, the second cause of the universe after the Father, the true and only-begotten Son of God, the Lord and God and King of all created things, the one who has received dominion and power, with divinity itself, and with might and honor from the Father;
[Moses] declares that the maker of the world and the creator of all things yielded to Christ himself, and to none other than his own clearly divine and first-born Word, the making of inferior things, and communed with him respecting the creation of man. “For,” says he, “God said, Let us make man in our image and in our likeness.” (Gen. 1:26) And another of the prophets confirms this, speaking of God in his hymns as follows: “He spake and they were made; he commanded and they were created.” (Ps. 33.9) He here introduces the Father and Maker as Ruler of all, commanding with a kingly nod, and second to him the divine Word, as carrying out the Father’s commands.
All who have excelled in righteousness and piety since the creation of man … have contemplated Him with the pure eyes of the mind, and have recognized Him and offered to Him the worship which is due Him as Son of God. But He, by no means neglectful of the reverence due to the Father, was appointed to teach the knowledge of the Father to them all. For instance, the Lord God appeared as a common man to Abraham while he was sitting at the oak of Mambre. And he, immediately falling down, although he saw a man with his eyes, nevertheless worshiped him as God, and sacrificed to him as Lord, and confessed that he was not ignorant of his identity when he uttered the words, “Lord, the judge of all the earth, wilt thou not execute righteous judgment?” (Gen. 18:25)
For it is unreasonable to suppose that the unbegotten and immutable essence of the almighty God was changed into the form of man or that it deceived the eyes of the beholders with the appearance of some created thing, and it is unreasonable to suppose, on the other hand, that the Scripture should falsely invent such things. … Nor is it admissible to suppose that the theophanies recorded were appearances of subordinate angels and ministers of God, for whenever any of these appeared to men, the Scripture does not conceal the fact, but calls them by name not God nor Lord, but angels, as it is easy to prove by numberless testimonies.
— Eusebius Pamphilius: Church History I.II. NPNF201.
Christ as Priest, King and Prophet
Thus Moses bestowed the name of our Saviour, Jesus Christ, as a mark of the highest honor, upon the two men who in his time surpassed all the rest of the people in virtue and glory; namely, upon the high priest and upon his own successor in the government.
And not only those who were honored with the high priesthood, and who for the sake of the symbol were anointed with especially prepared oil, were adorned with the name of Christ among the Hebrews, but also the kings whom the prophets anointed under the influence of the divine Spirit, and thus constituted, as it were, typical Christs. For they also bore in their own persons types of the royal and sovereign power of the true and only Christ, the divine Word who ruleth over all. And certain of the prophets themselves became, by the act of anointing, Christs in type, so that all these have reference to the true Christ, the divinely inspired and heavenly Word, who is the only high priest of all, and the only King of every creature, and the Father’s only supreme prophet of prophets.
Although he did not possess like honors with those whom we have mentioned, he is called Christ more than all of them. And as himself the true and only Christ of God, he has filled the whole earth with the truly august and sacred name of Christians, committing to his followers no longer types and images, but the uncovered virtues themselves, and a heavenly life in the very doctrines of truth. And he was not anointed with oil prepared from material substances, but, as befits divinity, with the divine Spirit himself, by participation in the unbegotten deity of the Father. And this is taught also again by Isaiah, who exclaims, as if in the person of Christ himself, “The Spirit of the Lord is upon me; therefore hath he anointed me. He hath sent me to preach the Gospel to the poor, to proclaim deliverance to captives, and recovery of sight to the blind.
— Eusebius Pamphilius: Church History I.III. NPNF201.
Christianity as the First and True Religion
Although it is clear that we are new and that this new name of Christians has really but recently been known among all nations, nevertheless our life and our conduct, with our doctrines of religion, have not been lately invented by us, but from the first creation of man, have been established by the natural understanding of divinely favored men of old.
That the Hebrew nation is not new, but is universally honored on account of its antiquity, is known to all. The books and writings of this people contain accounts of ancient men, rare indeed and few in number, but nevertheless distinguished for piety and righteousness and every other virtue.
All those who have enjoyed the testimony of righteousness, from Abraham himself back to the first man, were Christians in fact if not in name. For that which the name indicates, that the Christian man, through the knowledge and the teaching of Christ, is distinguished for temperance and righteousness, for patience in life and manly virtue, and for a profession of piety toward the one and only God over all—all that was zealously practiced by them not less than by us.
They also clearly knew the very Christ of God; for it has already been shown that he appeared unto Abraham, that he imparted revelations to Isaac, that he talked with Jacob, that he held converse with Moses and with the prophets that came after. Hence you will find those divinely favored men honored with the name of Christ, according to the passage which says of them, “Touch not my Christs, and do my prophets no harm.” (1 Chron. 16:22, Ps. 105:15)
— Eusebius Pamphilius: Church History I.IV. NPNF201.