What does 1 Corinthians 8:7 mean?
In some previous letter (1 Corinthians 7:1), the believers in Corinth appear to have pushed back against Paul's teaching to avoid eating food they know to have been offered to idols (1 Corinthians 8:1). He has agreed that the many gods and idols of Corinthian culture are not real: they do not actually exist (1 Corinthians 8:4–5). He understands that many Corinthian Christians know there is only one God.The problem, though, is that not every Corinthian Christian possessed this knowledge, even though it is true. Strange as that may sound to modern readers, belief in many gods was not a trivial concept in the ancient world. It was fundamental. Many converts to Christianity were deeply involved with idol worship prior to conversion. Paul seems to imply it is difficult for newer Christians in that pagan culture to think of idols as imaginary beings. When presented with idol food, their conscience tells them they are participating again in idolatry. If they eat, they violate their own conscience.
Paul then makes a remark which must be carefully understood, since it comes with powerful implications. He refers to the conscience of one who thinks eating idol food is a form of idolatry as "weak." Based on his prior statements, Paul appears to be saying that the eating of such meats—in and of itself—is not a sin. It's not wrong, since those idols are, in fact, imaginary and meat is just meat (1 Timothy 4:4). This is a key point in understanding this passage: there is no inherent sin in the act being questioned. Ideally, those who suffer from this weakness can grow beyond it.
However, that fact is not meant to be the end of a Christian's thought process. Paul does not condemn those with "weak" consciences for failing to recognize it is okay for Christians to eat idol food. What he does say is that to act in violation of their conscience will "destroy" them. Here, as he did with the Romans, Paul will insist that if someone acts against their conscience, doubting whether their action is pleasing to the Lord or not, he or she is condemned as sinful (Romans 14:23).
The importance of this idea, as it relates to Christian conduct, cannot be overstated. Few things in the Christian life are absolutely and totally forbidden—but all things, always, are subject to a submissive and obedient relationship with the Holy Spirit. Sometimes, attitude is what makes something a sin, not the act itself.