For the good Creator made all things good and the Maker of the universe is one, Who made the heaven and the earth, the sea and all that is in them. Of which whatever is granted to man for food and drink, is holy and clean after its kind. But if it is taken with immoderate greed, it is the excess that disgraces the eaters and drinkers, not the nature of the food or drink that defiles them. For all things, as the Apostle says, are clean to the clean. But to the defiled and unbelieving nothing is clean, but their mind and conscience is defiled.
–Saint Leo the Great (c. 400-461)