The Apostle Paul
Romans 14:14ESV·traditional attribution

I know and am persuaded in the Lord Jesus that nothing is unclean in itself, but it is unclean for anyone who thinks it unclean.

John Calvin Reformed @genevareformer

14. I know, etc. To anticipate their objection, who made such progress in the gospel of Christ as to make no distinction between meats, he first shows what must be thought of meats when viewed in themselves; and then he subjoins how sin is committed in the use of them.

Matthew Henry Presbyterian @wholebiblehenry

We have in this chapter, I. An account of the unhappy contention which had broken out in the Christian church. Our Master had foretold that offences would come; and, it seems, so they did, for want of that wisdom and love which would have prevented discord, and kept up union among them. 1.

Commenting on Romans 14:1-23

John Gill Reformed Baptist @doctorgill

I know and am persuaded by the Lord Jesus,.... As for the apostle's own sense and judgment about the distinction of meats, it was this, that there is nothing unclean of itself; that every creature, as originally made by God, is good; that what is eatable, or fit for food, may be eaten, whatever the Mosaic laws, being now abrogated, say to the contrary; and...