14 Object and general method of Dionysius in his 'Refutation and Defence.'
And the mere fact of Dionysius having made his defence about the matters on which these people harp suffices completely to condemn the Arians, and to demonstrate their malignity. For he wrote, not in angry controversy, but to defend himself on the points where he was under suspicion. But in defending himself against charges, what does he do if not, while disposing of every charge of which he was suspected, by this very fact convict the Arian madmen of malignity? But, to complete their confusions by means of what he wrote in his defence, come, let me set before you his actual words. For from them you will learn firstly that the Arians are malicious, secondly that Dionysius has nothing to do with their error. To begin with, then, he wrote his letter as in Refutation and in Defence. But this means, surely, that he aims at refuting false statements, and defends himself for what he has written; showing that he wrote not as Arius supposed, but that in mentioning what is said concerning the Lord in His human aspect, he was not ignorant that He was the Word and Wisdom undivided from the Father. Then he blames those who spoke against him for not quoting his language as a whole, but garbling it, and speaking not in good faith but disingenously and arbitrarily. And he compares them to those who used to impeach the letters of the blessed Apostle. But this complaint of his entirely clears him from sinister suspicion. For if he considers the detractors of Paul to be like his own, he shows precisely this, that he wrote as he did in Paul's sense. At any rate, in meeting severally the charges of his opponents, he explains all the passages cited by them: and, whereas in these latter he upsets Sabellius, in his subsequent letters he shows how sound and pious is his own faith. Accordingly whereas they would have it that Dionysius held that 'God was not always a Father, the Son did not always exist, but God existed apart from the Word, while the Son Himself was not before He was begotten: on the contrary, there was a time when He was not, for He is not eternal but has come later into being,'— see how he replies! Most of what he said, whether in the form of investigations, or collective inferences, or interrogatory refutations, or charges against his accusers, I omit because of the length of his discourses, inserting only what is strictly relevant to the charges against him. In answer to these, he writes after certain prefatory matter, in the first book inscribed 'Refutation and Defence' in the following terms.
Source: De Sententia Dionysii (New Advent)