"It is good neither to eat flesh, nor to drink wine, nor any thing whereby thy brother stumbleth, or is offended, or is made weak." (Romans 14:21)
Here is a sound biblical principle (not the only one, of course) given to Christians to help them evaluate whether or not to engage in certain practices which are neither explicitly endorsed nor prohibited in Scripture. The question is not whether the practice will hurt the strong Christian who engages in it, but whether his example might offend, or mislead, or discourage a weaker brother.
This matter of giving offense is quite serious in God's sight. "Give none offence, neither to the Jews, nor to the Gentiles, nor to the church of God" (1 Corinthians 10:32).
The problem of eating meat purchased from temple markets, after it had been offered in sacrifice to idols, is not an issue for many Christians today, but it was a very real problem to new believers in the first century. The principle given by Paul for deciding that issue is still valid for other issues of today (type of clothing, recreational games, smoking, etc.). As Paul expressed it, "Take heed lest by any means this liberty of yours become a stumblingblock to them that are weak. . . . when ye sin so against the brethren, and wound their weak conscience, ye sin against Christ. Wherefore, if meat make my brother to offend, I will eat no flesh while the world standeth, lest I make my brother to offend" (1 Corinthians 8:9, 12-13).
On the other side of the coin, the strong Christian should be careful not to take personal offense himself at something done by a fellow believer. "Great peace have they which love thy law: and nothing shall offend them" (Psalm 119:165). The rule for a mature, sincere, concerned Christian is to seek diligently neither to give offense nor take offense on any personal issue, by God's grace. HMM