Whatever has been rightly said by the heathen, we must appropriate to our uses.
Moreover, if those who are called philosophers, and especially the Platonists, have said aught that is true and in harmony with our faith, we are not only not to shrink from it, but to claim it for our own use from those who have unlawful possession of it. For, as the Egyptians had not only the idols and heavy burdens which the people of Israel hated and fled from, but also vessels and ornaments of gold and silver, and garments, which the same people when going out of Egypt appropriated to themselves, designing them for a better use, not doing this on their own authority, but by the command of God, the Egyptians themselves, in their ignorance, providing them with things which they themselves, were not making a good use of; in the same way all branches of heathen learning have not only false and superstitious fancies and heavy burdens of unnecessary toil, which every one of us, when going out under the leadership of Christ from the fellowship of the heathen, ought to abhor and avoid; but they contain also liberal instruction which is better adapted to the use of the truth, and some most excellent precepts of morality; and some truths in regard even to the worship of the One God are found among them. Now these are, so to speak, their gold and silver, which they did not create themselves, but dug out of the mines of God’s providence which are everywhere scattered abroad, and are perversely and unlawfully prostituting to the worship of devils. These, therefore, the Christian, when he separates himself in spirit from the miserable fellowship of these men, ought to take away from them, and to devote to their proper use in preaching the gospel. Their garments, also, that is, human institutions such as are adapted to that intercourse with men which is indispensable in this life, we must take and turn to a Christian use.
And what else have many good and faithful men among our brethren done? Do we not see with what a quantity of gold and silver and garments Cyprian, that most persuasive teacher and most blessed martyr, was loaded when he came out of Egypt? How much Lactantius brought with him? And Victorious, and Optatus, and Hilary, not to speak of living men! How much Greeks out of number have borrowed! And prior to all these, that most faithful servant of God, Moses, had done the same thing; for of him it is written that he was learned in all the wisdom of the Egyptians. And to none of all these would heathen superstition (especially in those times when, kicking against the yoke of Christ, it was persecuting the Christians) have ever furnished branches of knowledge it held useful, if it had suspected they were about to turn them to the use of worshipping the One God, and thereby overturning the vain worship of idols. But they gave their gold and their silver and their garments to the people of God as they were going out of Egypt, not knowing how the things they gave would be turned to the service of Christ. For what was done at the time of the exodus was no doubt a type prefiguring what happens now. And this I say without prejudice to any other interpretation that may be as good, or better.
De Doctrina Christiana 2.40