First Corinthians 5:6 warns that tolerating a known sin in a community is never harmless, because a small compromise tends to spread through the whole group. Paul is pointing to a specific case: the church in Corinth was proud of a member who was living in open sexual sin, and Paul calls that pride a serious mistake. He writes to the believers in Corinth, a busy port city with a mixed congregation, and he is speaking as the apostle who founded their church.
Your boasting is not good. Don’t you know that a little yeast leavens the whole lump?
1 Corinthians 5:6 (WEB)
What 1 Corinthians 5:6 Means
Paul begins with “your boasting is not good,” meaning the Corinthians were not celebrating a sign of spiritual maturity. They were proud of their tolerance, perhaps seeing themselves as generous or free from legalism, while ignoring the damage happening among them. The word “boasting” points to a community that felt good about its own openness rather than grieving over sin.
The picture of yeast comes next. In the ancient world, yeast was a small amount of leaven mixed into dough, and a little of it worked through the whole batch. Paul uses that everyday fact to show how one unaddressed sin does not stay contained. It affects attitudes, habits and the willingness of others to follow.
The verse does not promise that every sin will instantly be exposed or that the church will become perfect. It is a warning about what happens when wrongdoing is ignored, and it sets up the call in the verses that follow to clean out the old yeast.
The Context of 1 Corinthians 5:6
First Corinthians is a letter from the apostle Paul, traditionally dated to the mid-50s AD, written to a church he had helped start in Corinth. The congregation had divisions, disputes and a range of moral problems, and Paul addresses them one by one. Chapter 5 deals with a case of incest that the church had not disciplined, and Paul instructs them to act together in the name of the Lord.
The verses just before 5:6 describe Paul’s judgment on the man involved and the community’s responsibility to remove him from fellowship. Verse 6 then explains why this matters for everyone, not just for the one person. The verses after it, verses 7 and 8, connect the image of yeast to the Passover, urging the church to live as people set free by Christ. Read this way, the verse is not a general remark about all sin but a pastoral argument about a specific failure and its wider effects.
Key Phrases in 1 Corinthians 5:6
1 Corinthians 5:7
Purge out the old yeast, that you may be a new lump, even as you are unleavened. For indeed Christ, our Passover, has been sacrificed in our place.
(WEB)
This verse continues the yeast image and calls believers to purge out the old leaven. It shows that Paul’s concern is not only warning but a hopeful call to become the new batch that Christ’s sacrifice makes possible.
Hebrews 12:15
Looking carefully lest there be any man who falls short of the grace of God; lest any root of bitterness springing up trouble you, and many be defiled by it…
(WEB)
This passage also warns that a bitter root can spring up and defile many. It echoes the idea that a single unaddressed problem can spread through a community, and it urges believers to watch over one another carefully.
A Short Prayer From 1 Corinthians 5:6
Lord, you see the places in my life and in my church where I have grown comfortable with what I should be grieving. Show me any small compromise I have been excusing, and give me the courage to name it honestly. Help me not to take pride in tolerance when your holiness is at stake. Teach our community to love one another enough to speak the truth, and to rely on your grace to keep us clean and faithful. Amen.
