Library Eusebius of Caesarea On Ecclesiastical Theology
Book 1
Chapter 8: A statement of sound and ecclesiastical orthodoxy
Therefore the Church of God, cutting straight the direct and royal road, has rejected the other deviations. To her own nurslings she hands down the knowledge of the divine grace, teaching them, at the very mystery of regeneration, to confess that they believe in one God, the Father Almighty, and granting them to know this theology as perfect, exact, and complete. It hands down one God, setting itself apart from the polytheistic error of the Greeks; it knows him as Father, separating itself from the teaching of the Jews; and it confesses him as Almighty, turning away from the impiety of the godless heterodox.
For none of the heterodox would say that the Father of Christ is himself God Almighty; just as no one among the Jews, not knowing the only-begotten Son, would confess God to be Father; nor would a Greek say that he knows one God only. Therefore the Church, purging away the error of all these, proclaims the one God, teaching that he is both Father and Almighty: Father of the one Christ alone, but God, Creator, and Lord of all the rest. So too she hands down the only-begotten Son of God, Jesus Christ, begotten from the Father before all ages—not being the same as the Father, but existing and living by himself and being with him as truly Son; God from God, Light from Light, Life from Life; begotten from the Father for the salvation of the universe in ways unspeakable, ineffable, and altogether unknown and incomprehensible to us; and not subsisting like the rest of the things that have come into being, nor living a life resembling that of the things that came into being through him, but alone brought forth from the Father himself, and being Life itself (αὐτοζωή).
For it was fitting for the God who is over all to put forth this only-begotten offspring before every created thing and before all ages, as a kind of base and unbreakable foundation of the things that were to come into being through him. Therefore, before all the things that were to be, he begot the Son, as a ray of light, a fountain of life, and a treasury of good things, “in whom are hid all the treasures of wisdom and knowledge,” according to the divine Apostle.
Of such great good things the only good Father caused the Son to subsist: Life itself, giving life to the universe; Light itself, “the true” Light, illuminating every intellectual and rational essence; Word itself and Wisdom itself, wisely and rationally bringing all things into subsistence and governing them. For the sake of these things he alone, and no other, has been proclaimed and is the only-begotten Son of God.
Greek: Erich Klostermann, Eusebius Werke IV (Leipzig: Hinrichs, 1906), pp. 60–182. Digital Greek via Open Greek and Latin / Interlinea (CC BY-SA 4.0). English: study translation by Claude Opus 5.5 for BWAB Library—not the copyrighted CUA Press (Spoerl/Vinzent 2017) text. Technical terms and contested passages may be revised.