John Chrysostom

"For to the Lord belongeth the earth and the fulness thereof." Not to the devils. Now if the earth and the fruits and the beasts be all His, nothing is unclean: but it becomes unclean otherwise, from our intention and our disobedience. Wherefore he not only gave permission, but also...

Homily on 1 Corinthians 25 ↗

Theophylact of Ohrid

The earth is the Lord's, and not of demons. And if the earth is the Lord's, then the fruits, and the trees, and the animals are also the Lord's; and if all things are the Lord's, then by nature nothing is unclean, but everything depends on the mind of each person.

Commentary on 1 Corinthians ↗

Clement of Alexandria

And, "Let no one seek his own advantage, but also that of his neighbour," so as to be able at once to do and to teach, building and building up. For that "the earth is the Lord's, and the fulness thereof," is admitted; but the conscience of the weak is supported. "Conscience, I say, not his own, but that of the other; for why is my liberty judged of by another conscience? For if I by grace am partaker, why am I evil spoken of for that for which I give thanks? …

The Stromata Book 4 ↗