Miscellanies 6.15.126

For many reasons, then, the Scriptures conceal their sense: first, so that we may be inquirers and always keep awake for the discovery of the words of salvation; then, because it was not fitting for all to understand, lest they be harmed by taking in another sense what the Holy Spirit said for salvation. That is why the holy mysteries of the prophecies, kept for the chosen among men and for those selected from faith to knowledge, are veiled in parables. For the character of the Scriptures is parabolic, because the Lord too, though not of the world, came to men as one of the world. For he wore the whole of virtue, and he was to lead man, the nursling of the world, up through knowledge to the intelligible and proper realities, from world to world. That is why he used metaphorical writing. For such is the parable: a speech taken from something that is not the proper thing but resembles the proper thing, leading the one who understands to the true and proper thing; or, as some say, a diction that presents vividly through other terms what is meant in the proper sense.