Paul commands the Corinthian church to remove from fellowship a professing believer who is openly continuing in serious sexual sin. The church must judge clear, scandalous sin within its own body, guard its holiness in light of Christ’s sacrifice, and leave the judgment of outsiders to God.

Paul begins by saying that sexual immorality is actually being reported among the Corinthians, and not just any kind. A man is living with his father’s wife. This most likely refers to his stepmother, but either way the relationship is forbidden by God and shameful even by pagan standards. Yet the problem is not only the man’s sin. The church also stands guilty because it has become proud instead of mourning. Rather than grieving over this evil, they have tolerated it.

Paul therefore gives a clear judgment. Though he is absent in body, he has already judged the case because the sin is open and serious. When the church gathers, it must act in the name of the Lord Jesus and under His authority. This is not personal revenge, gossip, or private dislike. It is a formal act of church discipline.

Paul says to hand this man over to Satan for the destruction of the flesh, so that his spirit may be saved in the day of the Lord Jesus. The main point is that he must be put outside the fellowship of the church, outside the church’s sphere of recognized fellowship and care. This is a severe act, and Paul does not speak of it lightly. It may involve painful consequences. But the purpose is not mere punishment or hopeless rejection. The aim is that his sinful, fleshly rebellion may be broken and that he may finally be saved. The discipline is severe, but it is still meant to serve repentance and restoration.

Paul then explains why the church must act. Their boasting is not good. He uses the picture of yeast spreading through dough: a small amount affects the whole batch. In the same way, tolerated sin does not stay private. It spreads corruption through the congregation. That is why they must clean out the old yeast.

Yet Paul does not ground this command in mere moral effort or concern for appearances. He says, in effect, clean out the old yeast because you already are unleavened in Christ. The command rests on what Christ has done for them. Christ, our Passover lamb, has been sacrificed. Because His death has set God’s people apart, the church must live in a way that fits that redeemed identity. The call to holiness is not detached legalism. It flows from redemption.

When Paul says, "let us celebrate the festival," he is using Passover and unleavened bread imagery to describe the Christian life. His point here is not mainly to command calendar observance. His point is that the church, as a redeemed people, must live without the old yeast of sin. Vice and wickedness must be removed. In their place there must be sincerity and truth.

Paul then explains something he had written in an earlier letter. He told them not to associate with sexually immoral people, but he now clarifies that he did not mean immoral people in the world in general. He did not mean unbelievers who are sexually immoral, greedy, idolatrous, abusive, drunk, or dishonest. If Christians had to avoid all such people, they would have to leave the world entirely. So Paul is not teaching social withdrawal from unbelievers.

His command applies to someone who claims to be a Christian and yet continues in open, serious sin. If a person bears the Christian name and is sexually immoral, greedy, an idolater, verbally abusive, a drunkard, or a swindler, the church must not continue normal fellowship with that person. Paul says not even to eat with such a person. This likely includes ordinary meals as well as shared Christian fellowship, and it certainly means that the church must not treat such a person as though everything is spiritually well. Fellowship meals express recognition and acceptance, and that recognition must be withheld where there is open rebellion.

Paul then states the governing principle for the whole chapter. The church is not called to judge outsiders in this way. God will judge those outside. But the church is responsible to judge those inside—that is, professing believers within its fellowship—when the sin is manifest and serious. This does not contradict Paul’s earlier warning against proud, premature judgment. There he was speaking about judging hidden motives and exalting oneself. Here he is speaking about the church’s duty to deal with open sin among its own members. These are not the same kind of judgment.

So Paul ends with a firm command drawn from the Old Testament pattern of removing evil from among God’s people: remove the wicked person from among you. The church must keep clear boundaries. It must not pretend that scandalous, ongoing sin is compatible with Christian fellowship. Such discipline is painful, but it is necessary for the holiness of the church, the honor of Christ, and the hoped-for restoration of the sinner.

Key Truths: - Public, scandalous sin in the church must not be ignored. - The church must judge open sin among professing believers within its fellowship. - Church discipline is carried out under the authority of Jesus, not as personal retaliation. - "Handing over to Satan" refers mainly to exclusion from the church’s fellowship, with the aim of repentance and salvation. - Tolerated sin spreads and corrupts the whole church. - The church’s holiness is grounded in Christ’s sacrifice, not mere rule-keeping. - Believers are not called to withdraw from unbelievers in the world. - The command also applies beyond sexual sin to other serious, ongoing sins named in the passage.