The Enchiridion 21
21 Error, Though Not Always a Sin, is Always an Evil PL 40, 243
But as to those matters in regard to which our belief or disbelief, and indeed their truth or supposed truth or falsity, are of no importance whatever, so far as attaining the kingdom of God is concerned: to make a mistake in such matters is not to be looked on as a sin, or at least as a very small and trifling sin. In short, a mistake in matters of this kind, whatever its nature and magnitude, does not relate to the way of approach to God, which is the faith of Christ that “worketh by love.” For the “mistake pleasing to parents” in the case of the twin children was no deviation from this way; nor did the Apostle Peter deviate from this way, when, thinking that he saw a vision, he so mistook one thing for another, that, till the angel who delivered him had departed from him, he did not distinguish the real objects among which he was moving from the visionary objects of a dream; nor did the patriarch Jacob deviate from this way, when he believed that his son, who was really alive, had been slain by a beast. In the case of these and other false impressions of the same kind, we are indeed deceived, but our faith in God remains secure. We go astray, but we do not leave the way that leads us to Him. But yet these errors, though they are not sinful, are to be reckoned among the evils of this life which is so far made subject to vanity, that we receive what is false as if it were true, reject what is true as if it were false, and cling to what is uncertain as if it were certain. And although they do not trench upon that true and certain faith through which we reach eternal blessedness, yet they have much to do with that misery in which we are now living. And assuredly, if we were now in the enjoyment of the true and perfect happiness that lies before us, we should not be subject to any deception through any sense, whether of body or of mind.
Error non semper peccatum, sed semper malum. In quibus autem rebus nihil interest ad capessendum Dei regnum, utrum credantur, an non; vel utrum vera sive sint sive putentur, an falsa: in his errare, id est, aliud pro alio putare, non arbitrandum est esse peccatum; aut si est, minimum esse atque levissimum. Postremo, qualecumque illud et quantumcumque sit, ad illam viam non pertinet, qua imus ad Deum: quae via fides est Christi, quae per dilectionem operatur . Neque enim ab hac via deviabat in geminis filiis gratus ille parentibus error: aut ab hac via deviabat apostolus Petrus, quando se existimans visum videre, aliud pro alio sic putabat, ut a corporum imaginibus, in quibus se esse arbitrabatur, vera in quibus erat corpora non dignosceret, nisi cum ab illo angelus, per quem fuerat liberatus, abscessit: aut ab hac via deviabat Jacob patriarcha, quando viventem filium a bestia credebat occisum . In his atque hujusmodi falsitatibus, salva fide, quae in Deum nobis est, fallimur, et via non relicta quae ad illum ducit, erramus: qui errores etiamsi peccata non sunt, tamen in malis hujus vitae deputandi sunt, quae ita subjecta est vanitati, ut approbentur hic falsa pro veris, respuantur vera pro falsis, teneantur incerta pro certis. Quamvis enim haec ab ea fide absint, per quam veram certamque ad aeternam beatitudinem tendimus; ab ea tamen miseria non absunt, in qua adhuc sumus. Nullo modo quippe falleremur in aliquo vel animi vel corporis sensu, si jam vera illa atque perfecta felicitate frueremur.