69. Therefore amid the numerous dangers which threaten the faith, brevity of words must be employed sparingly, lest what is piously meant be thought to be impiously expressed, and a word be judged guilty of occasioning heresy when it has been used in conscientious and unsuspecting innocence. A Catholic about to state that the substance of the Father and the Son is one, must not begin at that point: nor hold this word all important as though true faith did not exist where the word was not used. He will be safe in asserting the one substance if he has first said that the Father is unbegotten, that the Son is born, that He draws His personal subsistence from the Father, that He is like the Father in might, honour and nature, that He is subject to the Father as to the Author of His being, that He did not commit robbery by making Himself equal with God, in whose form He remained, that He was obedient unto death. He did not spring from nothing, but was born. He is not incapable of birth but equally eternal. He is not the Father, but the Son begotten of Him. He is not any portion of God, but is whole God. He is not Himself the source but the image; the image of God born of God to be God. He is not a creature but is God. Not another God in the kind of His substance, but the one God in virtue of the essence of His exactly similar substance. God is not one in Person but in nature, for the Born and the Begetter have nothing different or unlike. After saying all this, he does not err in declaring one substance of the Father and the Son. Nay, if he now denies the one substance he sins.
69. Homousion quo loco tuto proferatur.---In his igitur tot et tam gravibus fidei periculis, verborum brevitas temperanda est; ne impie dici existimetur, quod pie intelligitur: ne secura atque innocente conscientia, per occasionem haereticam, reus sermo sit. 0526B Dicturus unam catholicus substantiam Patris et Filii, non inde incipiat: neque hoc quasi maximum teneat, tamquam sine hoc vera fides nulla sit. Tuto unam substantiam dicet, cum ante dixerit, Pater ingenitus est; Filius natus est, subsistit ex Patre, Patri similis est virtute, honore, natura. Patri subjectus est, ut auctori: nec se per rapinam Deo, cujus in forma manebat, aequavit; obediens usque ad mortem fuit. Non est ex nihilo, sed nativitas est. Non est innascibilis, sed cointemporalis. Non est pater, sed ex eo filius est. Non est portio aliqua, sed totus est. Non est auctor ipse, sed imago est: imago Dei ex Deo in Deum nata. Non est creatura, sed Deus est. Non alter Deus in genere substantiae, sed unus Deus per substantiae indifferentis essentiam. 0526C Non persona Deus unus est, sed natura: quia nihil in se diversum ac dissimile habeat natus et generans. Et post haec, unam substantiam Patris et Filii dicendo, non errat: aut unam substantiam negando, jam peccat.