For if because of food your brother is hurt, you are no longer walking according to love. Do not destroy with your food him for whom Christ died. Therefore do not let what is for you a good thing be spoken of as evil; for the kingdom of God is not eating and drinking, but righteousness and peace and joy in the Holy Spirit.
John Calvin comments: “...the price of the blood of Christ is wasted when a weak conscience is wounded, for the most contemptible brother has been redeemed by the blood of Christ. It is intolerable, therefore, that he should be destroyed for the gratification of the belly.” (Calvin’s New Testament Commentaries: Romans and Thessalonians, p.298, emphasis mine)
John Goodwin comments: “That the destruction here spoken of, whereunto the strong Christian is so earnestly admonished and dehorted by the apostle from exposing the weak, is not any temporal destruction, but that which is of body and soul forever, is more clear than to require proof.” (Redemption Redeemed, pp.83-84, emphasis mine)
Consider 1st Corinthians 10:24-33, which states: “Let no one seek his own good, but that of his neighbor. Eat anything that is sold in the meat market without asking questions for conscience’ sake; For the earth is the Lord’s, and all it contains. If one of the unbelievers invites you and you want to go, eat anything that is set before you without asking questions for conscience’ sake. But if anyone says to you, ‘This is meat sacrificed to idols,’ do not eat it, for the sake of the one who informed you, and for conscience’ sake; I mean not your own conscience, but the other man’s; for why is my freedom judged by another’s conscience? If I partake with thankfulness, why am I slandered concerning that for which I give thanks? Whether, then, you eat or drink or whatever you do, do all to the glory of God. Give no offense either to Jews or to Greeks or to the church of God; just as I also please all men in all things, not seeking my own profit but the profit of the many, so that they may be saved.”
In this context, the reference is not to a Christian brother, but a lost unbeliever who you are trying to win for the Lord, and hence Paul makes himself all things to all people so that he might win some. (1st Corinthians 9:19-23)