What does 1 Corinthians 5:11 mean?

Paul is giving to the church in Corinth, and to all Christian churches, a guideline for how we should respond when other believers begin to participate in actions that are clearly sinful. Should we ignore this issue, as the Corinthians had done with the man who was having an affair with his father's wife (1 Corinthians 5:1)? Clearly not. Instead, Paul's instruction is to remove that person from the community (1 Corinthians 5:2–5).

Now he adds that the rest of the church should not even continue to eat with such a person. In the previous verse, he clarified that this does not apply to those who are outside the church, unbelievers. Instead, he says here, this is about anyone who would call himself a brother—or herself a sister—in Christ (1 Corinthians 5:13).

Paul does not ask us to decide if that person is really a Christian or not. Instead, his instruction applies to anyone who claims to be a Christian. Paul's teaching here allows for the possibility that a self-professed Christian might at some point begin to participate in ongoing sexual immorality, greed, idol worship, angrily insulting others, regular drunkenness, or swindling people out of money.

Paul expresses two purposes for officially removing from the community those who are known to be living in sin. First, it provides protection for the community from getting caught up in either the sin itself or the consequences that sin will bring. Second, as he writes in 2 Thessalonians 3:14–15, such action may bring the sinful person to repentance, "If anyone does not obey what we say in this letter, take note of that person, and have nothing to do with him, that he may be ashamed. Do not regard him as an enemy, but warn him as a brother."

Other New Testament passages indicate that separating unrepentant sinners from the congregation is necessary for the health of the church, and the influence of the gospel among an unbelieving world (Jude 1:12; 2 Peter 2:2, 1 Peter 2:12).