Nicene and Post-Nicene Fathers, Ser. II, Vol. III:
Life and Works of Rufinus with Jerome's Apology Against Rufinus.: The attack on Epiphanius as a plagiarist of Origen is an outrage on the Bishops generally. Origen never wrote 6000 books.

21. To what point will not rashness reach when once the reins which check it are relaxed? After telling us of the excommunication of Hilary, the heretical book falsely bearing the name of Cyprian, the successive erasure and insertion in the work of Athanasius made while I was asleep, he as a last effort breaks forth into an attack upon the pope Epiphanius: the chagrin engendered in his heart because Epiphanius in the letter which he wrote to the bishop John had called him a heretic, he pours out in his apology for Origen, and comforts himself with these words:

“The whole truth, which has been hidden, must here be laid bare. It is impossible that any man should exercise so unrighteous a judgment as to judge unequally where the cases are equal. But the fact is, the prompters of those who defame Origen are men who either make it a habit to discourse in the churches at great length or write books, the whole of which, both books and discourse are taken from Origen. To prevent men therefore from discovering their plagiarism, the crime of which can be concealed so long as they act ungratefully towards their master, they deter all simple persons from reading him. One of them, who considers himself to have a necessity laid upon him to speak evil of Origen through every nation and tongue, as if that were to preach the Gospel, once declared in the audience of a vast multitude of the brethren that he had read six thousand of his books. If he read them, as he is wont to declare, in order to know what harm there was in him, ten or twenty books, or at most thirty, would have been sufficient for that knowledge. To read six thousand books is not like one who wants to know the harm and the errors that are in him, but like one who consecrates almost his whole life to studies conducted under his tuition. How then can he claim to be listened to when he blames those who, for the sake of instruction, have read a small portion of his works, taking care to maintain whole their own system of belief and their piety?”