John Calvin Commentary Romans 14:20

"Overthrow not for meat`s sake the work of God. All things indeed are clean; howbeit it is evil for that man who eateth with offence." — Romans 14:20 (ASV)

All things are indeed pure, etc. By saying that all things are pure, he makes a general declaration; and by adding that it is evil for a man to eat with offense, he makes an exception; as though he had said—“Meat is indeed good, but to give offense is bad.” Now, meat has been given to us so that we may eat it, provided love is observed: he then pollutes the use of pure meat who by it violates love. Therefore, he concludes that it is good to abstain from all things that tend to give offense to our brothers.

He mentions three things in order, to fall, to stumble, to be weakened: the meaning seems to be this—“Let no cause of falling, no, nor of stumbling, no, nor of weakening, be given to the brothers.” For to be weakened is less than to stumble, and to stumble is less than to fall. A person may be said to be weakened whose conscience wavers with doubt—to stumble when the conscience is disturbed by some greater perplexity, and to fall when the individual is somewhat alienated from attention to religion.