S. AURELII AUGUSTINI HIPPONENSIS EPISCOPI CONTRA MENDACIUM AD CONSENTIUM LIBER UNUS .
6. It remains, then, that what the Priscillianists think, according to the nefarious falsity of their heresy, of God, of the soul, of the body, and the rest, we hesitate not with truthful pity to condemn; but what they think of the right of telling a lie to hide the truth is to be to us and them (which God forbid!) a common dogma. This is so great an evil, that even though this attempt of ours, whereby we desire by means of a lie to catch them and change them, should so prosper that we do catch and change them, there is no gain that can compensate the damage of making ourselves wrong with them in order to set them right. For through this lie shall both we be in that respect perverse, and they but half corrected; seeing that their thinking it right to tell a lie on behalf of the truth is a fault which we do not correct in them, because we have learned and do teach the same thing, and lay it down that it is fit to be done, in order that we may be able to attain to the amending of them. Whom yet we amend not, for their fault, with which they think right to hide the truth, we take not away, rather we make ourselves faulty when by such a fault we seek them; nor do we find how we can believe them, when converted, to whom, while perverted, we have lied; lest haply what was done to them that they might be caught, they do to us when caught; not only because to do it hath been their wont, but because in us also, to whom they come, they find the same.
6. Remanet igitur, ut quod sentiunt Priscillianistae secundum haeresis suae nefariam falsitatem, de Deo, de anima, de corpore, et de caeteris rebus, non dubitemus veraci pietate damnare; quod autem sentiunt, ut veritas occultetur esse mentiendum, sit nobis, et illis, quod absit, dogma commune. Hoc tam magnum malum est, ut etiamsi conatus hic noster, 0523 quo eos per mendacium capere cupimus et mutare, ita prosperetur, ut eos capiamus atque mutemus, nullis lucris compensentur haec damna, quibus et nos cum ipsis pro illorum correctione depravamur. Per hoc namque mendacium et nos erimus ex ea parte perversi, et illi semicorrecti: quandoquidem istud, quod putant esse pro veritate mentiendum, non in eis corrigimus; quia idem nos didicimus et docemus, et fieri oportere praecipimus, ut ad eos emendandos pervenire possimus. Quos tamen non emendamus, quibus mendum , quo verum tegendum existimant, non auferimus; sed nos potius immendamur, cum pertale mendum eos quaerimus: nec invenimus quemadmodum eis conversis credere valeamus, quibus perversis mentiti sumus; ne forte quod ut caperentur sunt passi, faciant capti; non solum quia facere consueverunt, sed quia et in nobis, ad quos veniunt, hoc inveniunt.