Augustine of Hippo, on Titus 1:15

“All things are clean to the clean: but to them that are defiled, and to unbelievers, nothing is clean: but both their mind and their conscience are defiled.”

“With all this, no one is pressed to endure hardships for which he is unfit. Nothing is imposed on anyone against his will, nor is he condemned by the rest because he confesses himself too feeble to imitate them. They bear in mind how strongly Scripture enjoins charity on all.… Accordingly, all their endeavors are concerned not about the rejection of kinds of food as polluted but about the subjugation of inordinate desire and the maintenance of brotherly love.”

Imported from an open dataset — not yet checked against the printed edition.