1. We have in France an old teacher turned into a new theologian, who in his early days amused himself with dialectics, and now gives utterance to wild imaginations upon the Holy Scriptures. He is endeavouring again to quicken false opinions, long ago condemned and put to rest, not only his own, but those of others; and is adding fresh ones as well. I know not what there is in heaven above and in the earth beneath which he deigns to confess ignorance of: he raises his eyes to Heaven, and searches the deep things of God, and then returning to us, he brings back unspeakable words which it is not lawful for a man to utter, while he is presumptuously prepared to give a reason for everything, even of those things which are above reason; he presumes against reason and against faith. For what is more against reason than by reason to attempt to transcend reason? And what is more against faith than to be unwilling to believe what reason cannot attain? For instance, wishing to explain that saying of the wise man: He who is hasty to believe is light in mind (Ecclus. xix.4). He says that a hasty faith is one that believes before reason; when Solomon says this not of faith towards God, but of mutual belief amongst ourselves. For the blessed Pope Gregory denies plainly that faith towards God has any merit whatever if human reason furnishes it with proof. But he praises the Apostles, because they followed their Saviour when called but once (Hom. in Evang.26). He knows doubtless that this word was spoken as praise: At the hearing of the ear he obeyed me (Ps. xviii.44), that the Apostles were directly rebuked because they had been slow in believing (S. Mark xvi.14). Again, Mary is praised because she anticipated reason by faith, and Zacharias punished because he tempted faith by reason (S. Luke i.20, 45), and Abraham is commended in that against hope he believed in hope (Rom. iv.18).
2. But on the other hand our theologian says: "What is the use of speaking of doctrine unless what we wish to teach can be explained so as to be intelligible?" And so he promises understanding to his hearers, even on those most sublime and sacred truths which are hidden in the very bosom of our holy faith; and he places degrees in the Trinity, modes in the Majesty, numbers in the Eternity. He has laid down, for example, that God the Father is full power, the Son a certain kind of power, the Holy Spirit no power. And that the Son is related to the Father as force in particular to force in general, as species to genus, as a thing formed of material, to matter,  as man to animal, as a brazen seal to brass. Did Arius ever go further? Who can endure this? Who would not shut his ears to such sacrilegious words? Who does not shudder at such novel profanities of words and ideas? He says also that "the Holy Spirit proceeds indeed from the Father and the Son, but not from the substance of the Father or of the Son." Whence then? Perhaps from nothing, like everything created. But the Apostle does riot deny that they are of God, nor is he afraid to say: Of whom are all things (Rom. xi.36). Shall we say then that the Holy Spirit proceeds from the Father and the Son in no other way than all things do, that is, that He exists not essentially but by way of creation, and is therefore a creature like all other things. Or will this man, who is always seeking after new things, who invents what he does not find, affirms those things which are not, as though they are, will he find for himself some third way, in which he may produce Him from the Father and the Son? But, he says, "if He were of the substance of the Father, He would surely have been begotten, and so the Father would have two Sons." As though everything which is from any substance has always as its father that from which it is. For lice and phlegm and such things, are they sons of the flesh, and not rather of the substance of the flesh? Or worms produced by rotten wood, whence derive they their substance but from the wood? yet are they not sons of the wood. Again, moths have their substance from the substance of garments, but not their generation. And there are many instances of this kind.
3. Since he admits that the Holy Spirit is consubstantial with the Father and the Son, I wonder how an acute and learned man (as at least he thinks himself) can yet deny that He proceeds in substance from the Father and the Son, unless perchance he thinks that the two first persons proceed from the substance of the third. But this is an impious and unheard of opinion. But if neither He proceeds from their substance, nor They from His, where, I pray, is the consubstantiality? Let him then either confess with the Church that the Holy Spirit is of their substance, from whom He does not deny that He proceeds, or let him with Arius deny His consubstantiality, and openly preach His creation. Again he says, if the Son is of the substance of the Father, the Holy Spirit is not; they must differ from each other, not only because the Holy Spirit is not begotten, as the Son is, but also because the Son is of the substance of the Father, which the Holy Spirit is not. Of this last distinction the Catholic Church has hitherto known nothing. If we admit it, where is the Trinity? where is the Unity? If the Holy Spirit and the Son are really separated by this new enumeration of. differences, and if the Unity is split up, then especially let it be made plain that that distinction which he is endeavouring to make is a difference of substance. Moreover, if the Holy Spirit does not proceed from the substance of the Father and the Son, no Trinity remains, but a duality. For no Person is worthy to be admitted into the Trinity whose. substance is not the same as that of the others. Let him, therefore, cease to separate the procession of the Holy Spirit from the substance of the Father and the Son, lest by a double impiety he both take away number from the Trinity and attribute it to the Unity, each of which the Christian faith abhors. And, lest I seem in so great a matter to depend on human reasonings only, let him read the letter of Jerome to Avitus; and he will plainly see, that amongst the other blasphemies of Origen which he confutes, he also rejects this one, that, as he said, the Holy Spirit is not of the substance of the Father. The blessed Athanasius thus speaks in his book on the Undivided Trinity: "When I spoke of God alone I meant not the Person only of the Father, because I denied not that the Son and the Holy Spirit are of this same Substance of the Father."
 Materiatum; materia.