3 It is with no new doctrines that in their self-applauding perfidy they deceive the simple and untaught. They cannot, however, deceive theologians who meditate in the law of the Lord day and night. Let those blush then for their leaders and companions who say that a man may be “without sin” if he will, or, as the Greeks term it αναμάρτητος, “sinless.” As such a statement sounds intolerable to the Eastern churches, they profess indeed only to say that a man may be “without sin” and do not presume to allege that he may be “sinless” as well. As if, forsooth, “sinless” and “without sin” had different meanings; whereas the only difference between them is that Latin requires two words to express what Greek gives in one. If you adopt “without sin” and reject “sinless,” then condemn the preachers of sinlessness. But this you cannot do. You know very well what it is that you teach your pupils in private; and that while you say one thing with your lips you engrave another on your heart. To us, ignorant outsiders you speak in parables; but to your own followers you avow your secret meaning. And for this you claim the authority of scripture which says: “to the multitudes Jesus spoke in parables;” but to his own disciples He said: “it is given unto you to know the mysteries of the kingdom of heaven, but to them it is not given.”
But to return; I will shortly set forth the names of your leaders and companions to show you who those are of whose fellowship you make your boast. Manichæus says of his elect— whom he places among Plato's orbits in heaven— that they are free from all sin, and cannot sin even if they will. To so great heights have they attained in virtue that they laugh at the works of the flesh. Then there is Priscillian in Spain whose infamy makes him as bad as Manichæus, and whose disciples profess a high esteem for you. These are rash enough to claim for themselves the twofold credit of perfection and wisdom. Yet they shut themselves up alone with women and justify their sinful embraces by quoting the lines:
The almighty father takes the earth to wife;
Pouring upon her fertilizing rain,
That from her womb new harvest he may reap.
These heretics have affinities with Gnosticism which may be traced to the impious teaching of Basilides. It is from him that you derive the assertion that without knowledge of the law it is impossible to avoid sin. But why do I speak of Priscillian who has been condemned by the whole world and put to death by the secular sword? Evagrius of Ibera in Pontus who sends letters to virgins and monks and among others to her whose name bears witness to the blackness of her perfidy, has published a book of maxims on apathy, or, as we should say, impassivity or imperturbability; a state in which the mind ceases to be agitated and— to speak simply— becomes either a stone or a God. His work is widely read, in the East in Greek and in the West in a Latin translation made by his disciple Rufinus. He has also written a book which professes to be about monks and includes in it many not monks at all whom he declares to have been Origenists, and who have certainly been condemned by the bishops. I mean Ammonius, Eusebius, Euthymius, Evagrius himself, Horus, Isidorus, and many others whom it would be tedious to enumerate. He is careful, however, to do as the physicians, of whom Lucretius says:
To children bitter wormwood still they give
In cups with juice of sweetest honey smeared.
That is to say, he has set in the forefront of his book John, an undoubted Catholic and saint, by his means to introduce to the church the heretics mentioned farther on. But who can adequately characterize the rashness or madness which has led him to ascribe a book of the Pythagorean philosopher Xystus, a heathen who knew nothing of Christ, to Sixtus a martyr and bishop of the Roman church? In this work the subject of perfection is discussed at length in the light of the Pythagorean doctrine which makes man equal with God and of one substance with Him. Thus many not knowing that its author was a philosopher and supposing that they are reading the words of a martyr, drink of the golden cup of Babylon. Moreover in its pages there is no mention of prophets, patriarchs, apostles, or of Christ; so that according to Rufinus there has been a bishop and a martyr who had nothing to do with Christ. Such is the book from which you and your followers quote passages against the church. In the same way he played fast and loose with the name of the holy martyr Pamphilus ascribing to him the first of the six books in defence of Origen written by Eusebius of Cæsarea who is admitted by every body to have been an Arian. His object in doing so was of course to commend to Latin ears Origen's four wonderful books about First Principles.
Would you have me name another of your masters in heresy? Much of your teaching is traceable to Origen. For, to give one instance only, when he comments on the psalmist's words: “My reins also instruct me in the night season,” he maintains that when a holy man like yourself has reached perfection, he is free even at night from human infirmity and is not tempted by evil thoughts. You need not blush to avow yourself a follower of these men; it is of no use to disclaim their names when you adopt their blasphemies. Moreover, your teaching corresponds to Jovinian's second position. You must, therefore, take the answer which I have given to him as equally applicable to yourself. Where men's opinions are the same their destinies can hardly be different.
Source: Letters (New Advent)