The Prescription Against Heretics 35
35 Let Heretics Maintain Their Claims by a Definite and Intelligible Evidence. This the Only Method of Solving Their Questions. Catholics Appeal Always to Evidence Traceable to Apostolic Sources PL 2, 48
Challenged and refuted by us, according to these definitions, let all the heresies boldly on their part also advance similar rules to these against our doctrine, whether they be later than the apostles or contemporary with the apostles, provided they be different from them; provided also they were, by either a general or a specific censure, precondemned by them. For since they deny the truth of (our doctrine), they ought to prove that it also is heresy, refutable by the same rule as that by which they are themselves refuted; and at the same time to show us where we must seek the truth, which it is by this time evident has no existence amongst them. Our system is not behind any in date; on the contrary, it is earlier than all; and this fact will be the evidence of that truth which everywhere occupies the first place. The apostles, again, nowhere condemn it; they rather defend it,—a fact which will show that it comes from themselves. For that doctrine which they refrain from condemning, when they have condemned every strange opinion, they show to be their own, and on that ground too they defend it.
Nullam autem e contrario dictarum praescriptionum competere adversus nostram disciplinam.
His definitionibus provocatae a nobis et revictae haereses omnes, sive quae posterae, sive quae coaetaneae Apostolorum, dummodo diversae; sive generaliter, sive specialiter notatae ab eis, dummodo praedamnatae; audeant respondere et ipsae aliquas ejusmodi praescriptiones adversus nostram disciplinam. Si enim negant veritatem ejus, debent probare illam quoque haeresin esse, eadem forma revictam, qua ipsae revincuntur; et ostendere simul ubinam quaerenda sit veritas, quam apud illas non esse jam constat. Posterior nostra res non est, imo omnibus prior est: hoc erit testimonium veritatis, ubique occupantis principatum. Ab Apostolis utique non damnatur, imo defenditur: hoc erit indicium proprietatis. Quam enim non damnant, qui extraneam quamque damnaverunt, suam ostendunt, ideoque et defendunt.