Whoever, then, thinks that he understands the Holy Scriptures, or any part of them, but puts such an interpretation upon them as does not tend to build up this twofold love of God and our neighbor, does not yet understand them as he ought. If, on the other hand, a man draws a meaning from them that may be used for the building up of love, even though he does not happen upon the precise meaning which the author whom he reads intended to express in that place, his error is not pernicious, and he is wholly clear from the charge of deception. For there is involved in deception the intention to say what is false; and we find plenty of people who intend to deceive, but nobody who wishes to be deceived....
Whoever takes another meaning out of Scripture than the writer intended, goes astray, but not through any falsehood in Scripture. Nevertheless, as I was going to say, if his mistaken interpretation tends to build up love, which is the end of the commandment, he goes astray in much the same way as a man who by mistake quits the high road, but yet reaches through the fields the same place to which the road leads. He is to be corrected, however, and to be shown how much better it is not to quit the straight road, lest, if he get into a habit of going astray, he may sometimes take cross roads, or even go in the wrong direction altogether.
For if he takes up rashly a meaning which the author whom he is reading did not intend, he often falls in with other statements which he cannot harmonize with this meaning. And if he admits that these statements are true and certain, then it follows that the meaning he had put upon the former passage cannot be the true one: and so it comes to pass, one can hardly tell how, that, out of love for his own opinion, he begins to feel more angry with Scripture than he is with himself. And if he should once permit that evil to creep in, it will utterly destroy him. “For we walk by faith, not by sight.” Now faith will totter if the authority of Scripture begin to shake. And then, if faith totter, love itself will grow cold. For if a man has fallen from faith, he must necessarily also fall from love; for he cannot love what he does not believe to exist. But if he both believes and loves, then through good works, and through diligent attention to the precepts of morality, he comes to hope also that he shall attain the object of his love. And so these are the three things to which all knowledge and all prophecy are subservient: faith, hope, love....
And thus a man who is resting upon faith, hope and love, and who keeps a firm hold upon these, does not need the Scriptures except for the purpose of instructing others. Accordingly, many live without copies of the Scriptures, even in solitude, on the strength of these three graces. So that in their case, I think, the saying is already fulfilled: “Whether there be prophecies, they shall fail; whether there be tongues, they shall cease; whether there be knowledge, it shall vanish away.” Yet by means of these instruments (as they may be called), so great an edifice of faith and love has been built up in them, that, holding to what is perfect, they do not seek for what is only in part perfect—of course, I mean, so far as is possible in this life; for, in comparison with the future life, the life of no just and holy man is perfect here. Therefore the apostle says: “Now abideth faith, hope, charity, these three; but the greatest of these is charity:” because, when a man shall have reached the eternal world, while the other two graces will fail, love will remain greater and more assured.
Augustine of Hippo, "On Christian Doctrine," in St. Augustine’s City of God and Christian Doctrine, ed. Philip Schaff, trans. J. F. Shaw, vol. 2, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, First Series (Buffalo, NY: Christian Literature Company, 1887), Book I, Chapters 36-9, pp. 533-4.
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