In the Preface to Book iv. Jerome says he has been hindered in his work by the harassing of the Pelagian controversy. He regards Pelagius as reproducing the doctrines of impassibility and sinlessness taught by Pythagoras and Zeno, and revived by Origen, Rufinus, Evagrius Ponticus, and Jovinian. Their doctrines, he says, were promulgated chiefly in Sicily, Rhodes, and other islands; they were propagated secretly, and denied in public. They were full of malice, but were but dumb dogs, and were refuted in “certain writings,” probably those of Augustin; but he declares his intention of writing against them, which he did in his anti-Pelagian Dialogue.