De Decretis

“If there be an Image of the Invisible God, it is an invisible Image; nay, I will be bold to add, that, as being the likeness of the Father, never was it not. For when was that God, who, according to John, is called Light (for 'God is Light'), without a radiance of His proper glory, that a man should presume to assert the Son's origin of existence, as if before He was not? But when was not that Image of the Father's Ineffable and Nameless and Unutterable subsistence, that Expression and Word, and He that knows the Father? For let him understand well who dares to say, 'Once the Son was not,' that he is saying, 'Once Wisdom was not,' and 'Word was not,' and 'Life was not.'”

And again elsewhere he says:—

“But it is not innocent nor without peril, if because of our weakness of understanding we deprive God, as far as in us lies, of the Only-begotten Word ever co-existing with Him; and the Wisdom in which He rejoiced; else He must be conceived as not always possessed of joy.”

See, we are proving that this view has been transmitted from father to father; but you, O modern Jews and disciples of Caiaphas, how many fathers can you assign to your phrases? Not one of the understanding and wise; for all abhor you, but the devil alone; none but he is your father in this apostasy, who both in the beginning sowed you with the seed of this irreligion, and now persuades you to slander the Ecumenical Council, for committing to writing, not your doctrines, but that which from the beginning those who were eye-witnesses and ministers of the Word have handed down to us. For the faith which the Council has confessed in writing, that is the faith of the Catholic Church; to assert this, the blessed Fathers so expressed themselves while condemning the Arian heresy; and this is a chief reason why these apply themselves to calumniate the Council. For it is not the terms which trouble them, but that those terms prove them to be heretics, and presumptuous beyond other heresies.