What was the sin Paul confronts in this passage and why is it so serious?

Paul is dealing with a shocking case of sexual sin in the church. A man is living with “his father’s wife,” which means an incestuous relationship with his stepmother. Paul says even non‑Jewish people, who did not know God’s law, would be ashamed of this. The sin is made worse because it is open and known, and the church is doing nothing about it. By tolerating it, they damage their witness, dishonor Christ, and risk this sin spreading through the whole church.

Why does Paul say the Corinthians are "puffed up" instead of mourning?

Paul says they are “puffed up” because they are proud when they should be grieving. They may have been boasting about their gifts or their loving spirit, but at the same time they were ignoring open sin in their church. Instead of feeling broken and sad that someone among them was living this way, they acted as if everything was fine. Paul tells them they should have mourned over the sin and taken steps so that the man who did this would be removed from among them.

What does "a little leaven leaveneth the whole lump" mean here?

Leaven is like yeast that spreads through a whole batch of dough. Paul uses this picture to show how tolerated sin works in a church. If one open, unrepentant sin is allowed to remain, it will influence others, weaken people’s sense of right and wrong, and slowly affect the whole group. He is warning that they cannot treat this as a private matter or something small. Just as leaven quietly changes the dough, unchecked sin quietly changes the whole church.

Why does Paul call Christ "our passover" and talk about old leaven?

Paul is thinking of the Passover story, when God’s people removed all leaven from their houses and a lamb was killed so they could be spared. He says, “Christ our passover is sacrificed for us,” meaning Jesus is the true sacrifice who died so God would spare and save his people. Since that is true, believers should live like unleavened bread, without the “old leaven” of malice and wickedness. Instead, they are to live in sincerity and truth, showing a clean, honest life that fits what Christ has done.

Does this passage mean believers should avoid all sinners in everyday life?

Paul makes clear he is not telling Christians to avoid all people who sin in the world. He even says that if that were the rule, they “must needs go out of the world,” because sin is everywhere. His concern is different: if someone claims to be a brother or sister in Christ but chooses to live in open, unrepentant sin, the church must not treat that person as if everything is normal. The command to avoid close fellowship in that case is meant to show the seriousness of their choice and call them back.

Why does Paul say to "not to keep company" or "not to eat" with a sinning brother?

Paul tells them not to keep company or even eat with someone who calls himself a believer but lives in open sin and refuses to turn from it. Sharing normal, close fellowship would send the message that their behavior is acceptable. By stepping back from that closeness, the church shows that the person’s life does not match their claim to follow Christ. This separation is not meant to be cruel, but to wake the person up to the danger they are in and to protect the church from being drawn into the same sins.

What does this passage teach about judging those inside and outside the church?

Paul draws a clear line. He says he does not judge “those that are without,” meaning people outside the church. God himself will deal with them. But the church is responsible to judge “those that are within,” those who claim to belong to Christ. That means the church must lovingly confront and, if needed, discipline open, unrepentant sin among its members. This passage teaches that believers are not called to police the world, but they are called to care about holiness in their own community.

How should churches today apply Paul’s command to "put away from among yourselves that wicked person"?

This command points to removing an unrepentant person from the church’s fellowship when serious sin is public and ongoing. Today, that means church leaders, together with the congregation, should first call the person to repent with patience and clarity. If the person refuses and continues in the sin, the church may need to end formal membership and close fellowship with them. The aim is to guard the church’s witness and, more importantly, to bring the person to see their need to turn back to Christ.

1Cor.5.1

1 Corinthians 5:1

Q: What does it mean to "deliver such an one unto Satan for the destruction of the flesh"?

This line sounds very hard, but it describes a serious step of church discipline. To “deliver such a one unto Satan” means to put the man out of the church’s fellowship and protection, back into the world’s realm. The goal is not to ruin him, but that his sinful desires (“the flesh”) would be broken, so he will wake up, repent, and be saved in the day of the Lord Jesus. It is a painful step meant for his spiritual good, not revenge.

KJV

It is reported commonly that there is fornication among you, and such fornication as is not so much as named among the Gentiles, that one should have his father’s wife.

Immorality Rebuked

1 It is reported commonly that there is fornication among you, and such fornication as is not so much as named among the Gentiles, that one should have his father’s wife.

2 And ye are puffed up, and have not rather mourned, that he that hath done this deed might be taken away from among you.

3 For I verily, as absent in body, but present in Spirit, have judged already, as though I were present, concerning him that hath so done this deed,

4 In the name of our Lord Jesus Christ, when ye are gathered together, and my spirit, with the power of our Lord Jesus Christ,

5 To deliver such an one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus.

6 Your glorying is not good. Know ye not that a little leaven leaveneth the whole lump?

7 Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us:

8 Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened bread of sincerity and truth.

Expel the Immoral Brother

9 I wrote unto you in an epistle not to company with fornicators:

10 Yet not altogether with the fornicators of this world, or with the covetous, or extortioners, or with idolaters; for then must ye needs go out of the world.

11 But now I have written unto you not to keep company, if any man that is called a brother be a fornicator, or covetous, or an idolater, or a railer, or a drunkard, or an extortioner; with such an one no not to eat.

12 For what have I to do to judge them also that are without? do not ye judge them that are within?

13 But them that are without God judgeth. Therefore put away from among yourselves that wicked person.

Cross References

No cross references available for this verse.