Irenaeus of Lyons · a new plain-English translation from the original language
That the heretics follow neither the Scriptures nor the traditions.
For when they are refuted out of the Scriptures, they wheel around and lay blame on those Scriptures themselves, claiming they lack correctness and carry no authority, that their wording varies, and that the truth cannot be drawn from them by anyone ignorant of the tradition. That truth, they insist, was passed on not through writing but by a spoken voice: and for this reason Paul is said to have written, We utter wisdom among those made perfect, though it is not the wisdom belonging to this present age. And each of them says that this wisdom is what he himself has invented — a fiction, of course, so that, according to them, the truth may fittingly be found now in Valentinus, now in Marcion, now in Cerinthus, and afterward in Basilides, or even in him who argues against them, though he could say nothing salutary. For each of them, being altogether perverse, is not ashamed to preach, distorting the rule of truth to suit himself.
But when we appeal them again to that tradition which is from the Apostles, and which is preserved in the churches through the successions of presbyters, they set themselves against the tradition, claiming they are wiser than the presbyters and indeed than the Apostles too, and have uncovered the pure, unmixed truth. The Apostles, they claim, blended matters proper to the law together with the Savior's own sayings; and not the Apostles alone, but the Lord himself, spoke on one occasion out of the Demiurge, on another out of the intermediate realm, and on yet another out of the highest heights, whereas they alone, so they say, grasp with certainty, purely and honestly, the concealed mystery — which indeed is to blaspheme their own maker most shamelessly. It comes about, then, that they agree neither with the Scriptures nor with tradition. Against such people, my most beloved, our struggle is one in which they try, like slippery serpents, to escape on every side. For this reason they must be resisted on every side, if by refuting some of them we may be able to bring them round to conversion to the truth. For even if it is not easy for a soul caught in error to come to its senses, it is not altogether impossible to escape error when the truth is set before it.