I shall here insert the letter respecting the faith, written by Eusebius, bishop of Cæsarea, as it describes the effrontery of the Arians, who not only despise our fathers, but reject their own: it contains a convincing proof of their madness. They certainly honour Eusebius, because he adopted their sentiments, but yet they openly contradict his writings. He wrote this epistle to some of the Arians, who were accusing him, it seems, of treachery. The letter itself explains the writer's object.
Epistle of Eusebius, Bishop of Cæsarea, which he wrote from Nicæa when the great Council was assembled.
You will have probably learned from other sources what was decided respecting the faith of the church at the general council of Nicæa, for the fame of great transactions generally outruns the accurate account of them: but lest rumours not in strict accordance with the truth should reach you, I think it necessary to send to you, first, the formulary of faith originally proposed by us, and, next, the second, published with additions made to our terms. The following is our formulary, which was read in the presence of our most pious emperor, and declared to be couched in right and proper language.
The Faith put forth by us.
'As in our first catechetical instruction, and at the time of our baptism, we received from the bishops who were before us and as we have learned from the Holy Scriptures, and, alike as presbyters, and as bishops, were wont to believe and teach; so we now believe and thus declare our faith. It is as follows:—
'We believe in one God, Father Almighty, the Maker of all things, visible and invisible; and in one Lord Jesus Christ, the Word of God, God of God, Light of Light, Life of Life, Only-begotten Son, First-born of every creature, begotten of the Father before all worlds; by Whom all things were made; Who for our salvation was incarnate, and lived among men. He suffered and rose again the third day, and ascended to the Father; and He will come again in glory to judge the quick and the dead. We also believe in one Holy Ghost.
'We believe in the being and continual existence of each of these; that the Father is in truth the Father; the Son in truth the Son; the Holy Ghost in truth the Holy Ghost; as our Lord, when sending out His disciples to preach the Gospel, said, ' Go forth and teach all nations, baptizing them into the name of the Father, and of the Son, and of the Holy Ghost. ' We positively affirm that we hold this faith, that we have always held it, and that we adhere to it even unto death, condemning all ungodly heresy. We testify, as before God the Almighty and our Lord Jesus Christ, that we have thought thus from the heart, and from the soul, ever since we have known ourselves; and we have the means of showing, and, indeed, of convincing you, that we have always during the past thus believed and preached.'
When this formulary had been set forth by us, there was no room to gainsay it; but our beloved emperor himself was the first to testify that it was most orthodox, and that he coincided in opinion with it; and he exhorted the others to sign it, and to receive all the doctrine it contained, with the single addition of the one word— 'consubstantial.' He explained that this term implied no bodily condition or change, for that the Son did not derive His existence from the Father either by means of division or of abscission, since an immaterial, intellectual, and incorporeal nature could not be subject to any bodily condition or change. These things must be understood as bearing a divine and mysterious signification. Thus reasoned our wisest and most religious emperor. The addition of the word consubstantial has given occasion for the composition of the following formulary:—
The Creed published by the Council.
'We believe in one God, Father Almighty, Maker of all things visible and invisible. And in one Lord Jesus Christ, the Son of God, begotten of the Father; only-begotten, that is, of the substance of the Father, God of God, Light of Light, Very God of very God, begotten not made, being of one substance with the Father: by Whom all things were made both in heaven and on earth: Who for us men, and for our salvation, came down from heaven, and was incarnate, and was made man; He suffered, and rose gain the third day; He ascended into heaven, and is coming to judge both quick and dead. And we believe in the Holy Ghost. The holy Catholic and Apostolic Church anathematizes all who say that there was a time when the Son of God was not; that before He was begotten He was not; that He was made out of the non-existent; or that He is of a different essence and of a different substance from the Father; and that He is susceptible of variation or change.'
When they had set forth this formulary, we did not leave without examination that passage in which it is said that the Son is of the substance of the Father, and consubstantial with the Father. Questions and arguments thence arose, and the meaning of the terms was exactly tested. Accordingly they were led to confess that the word consubstantial signifies that the Son is of the Father, but not as being a part of the Father. We deemed it right to receive this opinion; for that is sound doctrine which teaches that the Son is of the Father, but not part of His substance. From the love of peace, and lest we should fall from the true belief, we also accept this view, neither do we reject the term 'consubstantial.' For the same reason we admitted the expression, 'begotten, but not made;' for they alleged that the word 'made' applies generally to all things which were created by the Son, to which the Son is in no respect similar; and that consequently He is not a created thing, like the things made by Him, but is of a substance superior to all created objects. The Holy Scriptures teach Him to be begotten of the Father, by a mode of generation which is incomprehensible and inexplicable to all created beings. So also the term 'of one substance with the Father,' when investigated, was accepted not in accordance with bodily relations or similarity to mortal beings. For it was also shown that it does not either imply division of substance, nor abscission, nor any modification or change or diminution in the power of the Father, all of which are alien from the nature of the unbegotten Father. It was concluded that the expression ' being of one substance with the Father,' implies that the Son of God does not resemble, in any one respect, the creatures which He has made; but that to the Father alone, who begot Him, He is in all points perfectly like: for He is of the essence and of the substance of none save of the Father. This interpretation having been given of the doctrine, it appeared right to us to assent to it, especially as we were aware that of the ancients some learned and celebrated bishops and writers have used the term 'consubstantial' with respect to the divinity of the Father and of the Son.
Source: Ecclesiastical History (New Advent)