Nicene and Post-Nicene Fathers, Vol. II:
On Christian Doctrine: Chapter 5

Chapter 5.—It is a Wretched Slavery Which Takes the Figurative Expressions of Scripture in a Literal Sense.

9.  But the ambiguities of metaphorical words, about which I am next to speak, demand no ordinary care and diligence.  In the first place, we must beware of taking a figurative expression literally.  For the saying of the apostle applies in this case too:  “The letter killeth, but the spirit giveth life.” 1854   For when what is said figuratively is taken as if it were said literally, it is understood in a carnal manner.  And nothing is more fittingly called the death of the soul than when that in it which raises it above the brutes, the intelligence namely, is put in subjection to the flesh by a blind adherence to the letter.  For he who follows the letter takes figurative words as if they were proper, and does not carry out what is indicated by a proper word into its secondary signification; but, if he hears of the Sabbath, for example, thinks of nothing but the one day out of seven which recurs in constant succession; and when he hears of a sacrifice, does not carry his thoughts beyond the customary offerings of victims from the flock, and of the fruits of the earth.  Now it is surely a miserable slavery of the soul to take signs for things, and to be unable to lift the eye of the mind above what is corporeal and created, that it may drink in eternal light.

Footnotes

2 Cor. 3.6.