Augustine of Hippo : God's pastures are good, and God's springs are pure. We have them in the holy Scriptures. — SERMON 47:9 Gregory the Dialogist : For indeed the shepherds drink most pure water, when with a right understanding they imbibe the streams of truth. But to foul the same water with their feet is to corrupt the studies of holy meditation by evil living. And verily the sheep drink the water fouled by their feet, when any of those subject to them follow not the words which they hear, but only imitate the bad examples which they see. Thirsting for the things said, but perverted by the works observed, they take in mud with their draughts, as from polluted fountains. — Pastoral Rule, Part 1, Chapter 2 Jerome : But these things he spoke against the shepherds: now he speaks to the sheep, that is, to the people: and to the flock of both kinds of livestock, that is, the sheep and the goats: and not only to the sheep and goats, but also to the rams and the bucks, who are the leaders in the flocks, to whom he says: Was it not enough for you to feed on the good pastures of the Scriptures? But in addition, you were trampling on the remnants of your pastures with your feet. And while you were drinking the purest waters of God's teachings, you were disturbing the remaining waters with your feet, so that my people would eat and drink trampled pastures and tainted waters because of your fault, which in itself was good but became corrupted and violated. Indeed, this is what all heretics do, they pick apart the words of the Scriptures and, to the best of their ability, stain them. But even the ecclesiastical men who do not preserve the truth of the doctrines, but instead fabricate them from their own hearts, and hold their presumption as a teacher, are held captive by a similar error. — Commentary on Ezekiel