1. The perspicuity of the Scriptures is a quality agreeing with them as with a sign, according. to which quality they are adapted clearly to reveal the conceptions, whose signs are the words comprised in the Scriptures, to those persons to whom the Scriptures are administered according to the benevolent providence of God.
2. That perspicuity is a quality which agrees with the Scriptures, is proved from its cause and its end.
(1.) In cause, we consider the wisdom and goodness of the author, who, according to his wisdom knew, and according to his goodness willed, clearly and well to enunciate or declare the meanings of his own mind.
(2.) In the end is the duty of those to whom the Scriptures are directed, and who, through the decree of God, cannot attain to salvation without this knowledge.
3. This perspicuity comes distinctly to be considered both with regard to its object and its subject. For all things [in the Scriptures] are not equally perspicuous, nor is every thing alike perspicuous to all persons; but in the epistle of St. Paul, some things occur which "are hard to be understood;" and "the gospel is hid, or concealed, to them who are lost, in whom the god of this world hath blinded the minds of them who believe not."
4. But those senses or meanings, the knowledge and belief of which are simply necessary to salvation, are revealed in the Scriptures with such plainness, that they can be perceived even by the most simple of mankind, provided they be able duly to exercise their reason.
5. But they are perspicuous to those alone who, being illuminated by the light of the Holy Spirit, have eyes to see, and a mind to understand and discern. For any color whatever, though sufficiently illuminated by the light, is not seen except by the eye which is endued with the power of seeing, as with an inward light.
6. But even in those things which are necessary to be known and believed in order to salvation, the law must be distinguished from the gospel, especially in that part which relates to Jesus Christ crucified and raised up again. For even the gentiles, who are aliens from Christ, have "the work of the law written in their hearts," though this is not saving, except by the addition of the internal illumination and inspiration of God; but "the doctrine of the cross, which is foolishness and a stumbling block to the natural man," is not perceived without the revelation of the Spirit.
7. In the Scriptures, some things may be found so difficult to be understood, that men of the quickest and most perspicacious genius may, in attaining to an understanding of those things, have a subject on which to bestow their labors during the whole course of their lives. But God has so finely attempered the Scripture, that they can neither be read without profit, nor, after having been perused and reperused innumerable times, can they be put aside through aversion or disgust.