Vincent of Lérins on the perspicuity of scripture

[4.] I have often then inquired earnestly and attentively of very many men eminent for sanctity and learning, how and by what sure and so to speak universal rule I may be able to distinguish the truth of Catholic faith from the falsehood of heretical pravity; and I have always, and in almost every instance, received an answer to this effect: That whether I or any one else should wish to detect the frauds and avoid the snares of heretics as they rise, and to continue sound and complete in the Catholic faith, we must, the Lord helping, fortify our own belief in two ways; first, by the authority of the Divine Law, and then, by the Tradition of the Catholic Church.

[5.] But here some one perhaps will ask, Since the canon of Scripture is complete, and sufficient of itself for everything, and more than sufficient, what need is there to join with it the authority of the Church’s interpretation? For this reason,—because, owing to the depth of Holy Scripture, all do not accept it in one and the same sense, but one understands its words in one way, another in another; so that it seems to be capable of as many interpretations as there are interpreters. For Novatian expounds it one way, Sabellius another, Donatus another, Arius, Eunomius, Macedonius, another, Photinus, Apollinaris, Priscillian, another, Iovinian, Pelagius, Celestius, another, lastly, Nestorius another. Therefore, it is very necessary, on account of so great intricacies of such various error, that the rule for the right understanding of the prophets and apostles should be framed in accordance with the standard of Ecclesiastical and Catholic interpretation.

[64.] Here, possibly, some one may ask, Do heretics also appeal to Scripture? They do indeed, and with a vengeance; for you may see them scamper through every single book of Holy Scripture,—through the books of Moses, the books of Kings, the Psalms, the Epistles, the Gospels, the Prophets. Whether among their own people, or among strangers, in private or in public, in speaking or in writing, at convivial meetings, or in the streets, hardly ever do they bring forward anything of their own which they do not endeavour to shelter under words of Scripture. Read the works of Paul of Samosata, of Priscillian, of Eunomius, of Jovinian, and the rest of those pests, and you will see an infinite heap of instances, hardly a single page, which does not bristle with plausible quotations from the New Testament or the Old.

[65.] But the more secretly they conceal themselves under shelter of the Divine Law, so much the more are they to be feared and guarded against. For they know that the evil stench of their doctrine will hardly find acceptance with any one if it be exhaled pure and simple. They sprinkle it over, therefore, with the perfume of heavenly language, in order that one who would be ready to despise human error, may hesitate to condemn divine words. They do, in fact, what nurses do when they would prepare some bitter draught for children; they smear the edge of the cup all round with honey, that the unsuspecting child, having first tasted the sweet, may have no fear of the bitter. So too do these act, who disguise poisonous herbs and noxious juices under the names of medicines, so that no one almost, when he reads the label, suspects the poison. (Vincent of Lérins, The Commonitory)