I Corinthians 5:6 · Bible study
1 Corinthians 5:6 Commentary: Boasting, Yeast, and Church Purity
Greek · 11 what the commentators say
Meaning in one sentence
Paul rebukes Corinthian boasting while incest is tolerated, warning that a little yeast, sin, spreads through the whole church.
Research Summary
- Meaning: Boasting while tolerating sin is foolish because a small amount of tolerated sin corrupts the entire church community.
- Key words: καύχημα (kauchēma, object of boasting, not the act); ζύμη (zūmē, leaven, symbol of moral corruption); φύραμα (phurama, lump of dough, the unified church).
- Main debate: Whether καύχημα means the act of boasting (KJV: 'your glorying') or the ground of boasting (Vincent, Lange, Cambridge). The context favours the latter: they boast about their church's condition, which is actually rotten.
- Theological theme: Corporate holiness and church discipline rooted in the Passover sacrifice of Christ. The gospel demands purity; discipline is an act of love for the whole body.
- Best use: A teaching text on the relationship between grace and discipline, or a warning against pride that ignores hidden sin.
Translation Comparison
BSB Berean Standard Bible 2020
Your boasting is not good. Do you not know that a little leaven works through the whole batch of dough?
WEB World English Bible 2000
Your boasting is not good. Don’t you know that a little yeast leavens the whole lump?
KJV King James Version 1769
Your glorying is not good. Know ye not that a little leaven leaveneth the whole lump?
ASV American Standard Version 1901
Your glorying is not good. Know ye not that a little leaven leaveneth the whole lump?
YLT Young's Literal Translation 1898
Not good is your glorying; have ye not known that a little leaven the whole lump doth leaven?
Darby Darby Bible 1890
Your boasting [is] not good. Do ye not know that a little leaven leavens the whole lump?
Douay-Rheims Douay-Rheims Bible 1899
Your glorying is not good. Know you not that a little leaven corrupteth the whole lump?
Translations in other languages (10 available)
No es buena vuestra jactancia. ¿ No sabéis que un poco de levadura leuda toda la masa?
Vosso orgulho não é bom. Não sabeis que um pouco de fermento faz levedar toda a massa?
C’ est bien à tort que vous vous glorifiez. Ne savez-vous pas qu’ un peu de levain fait lever toute la pâte?
Euer Ruhm ist nicht fein. Wisset ihr nicht, daß ein wenig Sauerteig den ganzen Teig versäuert?
Uw roem is niet goed. Weet gij niet, dat een weinig zuurdesem het gehele deeg zuur maakt?
Il vostro vantarvi non è buono. Non sapete voi che un po’ di lievito fa lievitare tutta la pasta?
Nie dobrać to chluba wasza. Azaż nie wiecie, iż trochę kwasu wszystko zaczynienie zakwasza?
Нечем вам хвалиться. Разве не знаете, что малая закваска квасит все тесто?
你們 這自誇 是不 好的。豈不 知 一點 麵酵 能使全 團 發起來嗎？
This pride of yours is not good. Do you not see that a little leaven makes a change in all the mass?
Verse in Context
Original Language (Koine Greek)
New Testament · Koine Greek · I Corinthians 5:6
Source: STEPBible TAGNT/TEHB (CC-BY 4.0). Click or tap a morphology code to see the full parsing.
Scholars' Consensus
Commentators unanimously agree that Paul confronts the Corinthians for boasting while tolerating a serious sin, incest, within their congregation. The phrase 'Your boasting is not good' strikes at their misplaced pride. Vincent's Word Studies notes that the Greek noun καύχημα (kauchēma) refers not to the act of boasting but to the object of boasting: the Corinthians' self-congratulatory view of their church's condition. Barnes and Calvin concur that boasting over gifts and growth is senseless when such corruption remains unaddressed. The proverb 'a little yeast leavens the whole lump' is then applied: unrebuked sin spreads like leaven through dough. Wesley summarises: 'One sin, or one sinner […] diffuses guilt and infection through the whole congregation.' The commentators therefore see this verse as a foundational call for church discipline, not from harshness, but from the sober recognition that tolerated evil endangers the whole body.
How settled is the interpretation?
Interpretive difficulty: Medium
Main views:
- Boasting as the act of glorying: KJV and older translations render 'your glorying' as the activity, implying the Corinthians' act of boasting is wrong regardless of circumstance. Supported by the immediate context of arrogance (5:2).
- Boasting as the ground of glorying: Vincent, Lange and the Cambridge Bible argue that καύχημα means 'that wherein one glories'—their corrupt church condition. This aligns with Paul's critique of their distorted values and better fits the rhetorical question 'Don't you know?'
What is clear: A little sin tolerated in the church will corrupt the whole community, and boasting under such conditions is therefore inappropriate.
What Scholars Agree and Debate
| Topic | Agreed | Debated |
|---|---|---|
| Meaning of the yeast metaphor | All commentators agree the yeast (ζύμη) symbolises moral corruption that spreads from one tolerated sin to the whole congregation. | Some traditions (e.g., Baptists) focus on the need for formal church discipline and excommunication; others (e.g., Wesleyan) apply it to personal heart-purification and the danger of any tolerated sin. |
| Target of 'boasting' | It is agreed that Paul denounces the Corinthians' pride as inconsistent with their spiritual state. | The KJV translates καύχημα as 'glorying' (the act), while Vincent and Lange read it as 'that in which you glory' (the object). The difference changes the emphasis: is the fault that they are boasting, or that what they boast about is rotten? Most modern translations (WEB, BSB) follow the latter. |
| Scope of the warning | The proverb is understood as a principle: unaddressed evil spreads. | Protestant traditions (Reformed, Baptist) stress this as a biblical basis for excommunication and separation from professing believers in unrepentant sin. Others (some Catholic and Orthodox) see it as calling for pastoral correction and sacramental confession rather than outright expulsion. |
Historical & Cultural Context
First-century Corinth sat at a busy crossroads of trade and immorality. The church there had grown proud of its spiritual gifts and teachers (1 Corinthians 3:21; 4:18-19), yet it had allowed a man to live in incest with his stepmother, a relationship so shocking that even pagan society condemned it (5:1). Paul's reprimand in 5:6 is sharp: their boasting is hollow while such sin festers unnoticed.
The metaphor of yeast leavening a lump of dough was a common proverb in both Greek and Jewish settings. Gill points to rabbinic use of the same saying. In Jewish culture, leaven regularly symbolised corruption and evil. During Passover, all leaven was removed from homes (Exodus 12:15). Paul draws directly on that imagery in the next verse: 'Christ, our Passover, has been sacrificed' (v7). The Corinthians would have understood, a little yeast contaminates the whole batch. Paul applies the image to moral corruption: one tolerated sinner infects the entire community.
The Corinthians' misplaced glorying (καύχημα) reflects their broader spiritual problem. They boasted of their wisdom and freedom, yet failed to see the cancer in their midst. The apostle's rhetorical question, 'Don't you know?', implies they should have known better. Paul expects them to connect the dots between their pride and their negligence.
This background matters because it shows Paul is not imposing an unfamiliar rule. He is pressing home a truth the Corinthians already accepted in everyday life: a small contaminant ruins the whole. The same principle governs the church. The gospel of grace does not make discipline optional; it makes it urgent, because the holiness of the whole body is at stake.
Textual Notes
No significant textual variants are noted in the consulted sources for 1 Corinthians 5:6. The only variants in the surrounding passage concern the inclusion of 'for us' in verse 7 and the presence of 'therefore' in some manuscripts of verse 7 and verse 13, but these do not affect verse 6 itself. The transmitted Greek text is stable and presents no serious editorial issues.
Reception History
This verse has been a cornerstone of church discipline throughout Christian history. Early church fathers such as Tertullian and Cyprian referenced it to justify the exclusion of unrepentant sinners from communion. During the Reformation, Calvin and the Geneva Bible commentators used the verse to argue that churches must actively purge corrupt members to maintain purity. In the Wesleyan tradition, John Wesley emphasised the spreading nature of sin and the need for class meetings as a means of mutual accountability. The image of leaven also appears in hymnody, where believers are urged to 'purge the old leaven' in songs about Christian purity. Across traditions, the verse has served as a sober reminder that holiness is not a private matter, it belongs to the whole people of God.
Preaching This Verse
Three-point outline
- Misplaced boasting blinds the church to its own rot. The Corinthians prided themselves on gifts and status while ignoring grave sin. Boasting is never good; boasting while sin festers is fatal self-deception.
- A little yeast leavens the whole lump. Tolerating even a small sin in the congregation or in individual life spreads corruption. The proverb warns that infection is inevitable if the contaminant is not removed.
- Purification requires decisive action. Paul does not counsel patience or gentle conversation alone; he commands purging. The call to remove the 'old yeast' (v7) points to discipline that protects the body and restores the sinner.
Five-point outline
- What we boast about reveals what we value. The Corinthians valued status, teachers, and apparent success. They valued appearance more than holiness.
- Boasting without repentance is self-deception. A church can grow in numbers and gifts while decaying from within. Paul will not let them ignore the decay.
- The yeast metaphor shows the power of small corruption. Leaven works silently, invisibly, until the whole is affected. So does sin.
- Church discipline is not punishment; it is protection. Removing the yeast preserves the lump. Discipline aims to save both the individual (v5, 'that the spirit may be saved') and the corporate body.
- Christ our Passover is the basis for a new, unleavened life. Because Christ died, believers are called to live in sincerity and truth (v8). Discipline flows from the gospel, not legalism.
Illustration hooks
- A single mould spot on a loaf of bread, if you cut it off, the rest is safe. If you leave it, the mould spreads until the entire loaf is ruined.
- A small crack in a dam that goes unrepaired. At first it seems harmless, but the pressure of the water widens it until the whole structure fails.
- A family that ignores one member's destructive habit out of a desire to keep peace. Over time the habit affects every relationship and the home becomes unhealthy.
Questions your congregation is asking
- Why does Paul seem so harsh here? Doesn't grace cover all sin?
- What counts as 'yeast' in our church today, is it only sexual sin, or also gossip, pride, and greed?
- How do we practice church discipline without becoming judgmental or legalistic?
Leading a Discussion
The Corinthians boasted as if everything were fine, while a shocking sin was tolerated among them. Paul's short, sharp proverb pulls the mask off their pride. This passage invites us to examine where we might overlook 'small' sins in our own lives or in our church community, and what it really means to take holiness seriously without losing grace.
Discussion questions
- Read 1 Corinthians 5:1-6. What details in the opening verses show the seriousness of the situation? How does the tone change when Paul says 'your boasting is not good'?
- Why would the Corinthians have been boasting? What might they have been proud of, and why was that pride so misplaced? (See 1 Corinthians 4:18-19 for a clue.)
- The proverb 'a little yeast leavens the whole lump' was a common saying. What does it teach about the nature of sin in a community? Can you think of modern examples where a small problem spread?
- Paul uses yeast to describe moral corruption. In Matthew 13:33, Jesus uses yeast to describe the spread of the Kingdom. Why the same image for different effects? What does that tell us about interpreting metaphors in context?
- The Corinthians' boasting was 'not good' (kalon, beautiful, fitting). What makes boasting ugly in this situation? When is confidence in God's work appropriate, and when does it become hollow pride?
- Verse 7 commands: 'Purge out the old yeast.' What would that look like practically in a local church today? How do we balance the call to purity with the call to welcome sinners?
- Where might there be 'a little yeast' in your own life or small group that needs attention, not to condemn but to protect the whole?
Word Study
The key original-language words in this verse. Select any word for its full lexicon entry — meaning, every occurrence in Scripture, and related words.
Cross-References
Source: Treasury of Scripture Knowledge (TSK, public domain)
| Matthew 13:33 | He spoke another parable to them. “The Kingdom of Heaven is like yeast which a woman took and hid in three measures of meal, until it was all leavened.” |
| Matthew 16:6 | Jesus said to them, “Take heed and beware of the yeast of the Pharisees and Sadducees.” |
| Matthew 16:12 | Then they understood that he didn’t tell them to beware of the yeast of bread, but of the teaching of the Pharisees and Sadducees. |
| Luke 13:21 | It is like yeast, which a woman took and hid in three measures of flour, until it was all leavened.” |
| I Corinthians 3:21 | Therefore let no one boast in men. For all things are yours, |
| I Corinthians 4:18 | Now some are puffed up, as though I were not coming to you. |
| I Corinthians 4:19 | But I will come to you shortly, if the Lord is willing. And I will know, not the word of those who are puffed up, but the power. |
| I Corinthians 5:2 | You are arrogant, and didn’t mourn instead, that he who had done this deed might be removed from among you. |
Interlinear and lexical data from STEPBible (CC BY 4.0). Cross-reference data from OpenBible.info (CC BY 4.0). Commentaries are public domain.
For personal reflection
Read the devotional page — prayer, application, and "for families"
What the Commentators Say
10 public-domain commentaries, condensed into plain language.
Adam Clarke's Commentary Methodist/Wesleyan 1826
Clarke charges the Corinthians with pride in their knowledge and teachers while ignoring blatant corruption in the church. He warns that allowing the incestuous man to remain will spread impurity and ruin the entire Christian community in Corinth.
Barnes' Notes on the Bible Protestant 1832
Barnes argues that boasting is always wrong, but especially so when unaddressed sin threatens to corrupt the entire church. People boast only because they are blind to their real condition. A single tolerated sin, like leaven, will spread through the whole body until it is removed by discipline.
Calvin's Commentaries Reformed 1564
Calvin notes that Paul is not condemning all glorying here, but specifically the Corinthians' empty boasting while tolerating serious sin in their midst. What makes their pride so foolish is that they celebrate their supposed excellence while ignoring a corrupting influence within the church. The leaven proverb warns that even one unrepentant sinner can infect the whole community.
Geneva Bible Notes Reformed 1599
The Geneva Notes warn that taking pride in the church while refusing to discipline flagrant sin is a dangerous inconsistency. A small amount of corrupting influence, like leaven in dough, will eventually contaminate the entire congregation if left unchecked.
Gill's Exposition of the Bible Baptist 1748
Gill focuses on the danger of boasting while a serious sin goes unchecked. He applies the common proverb about leaven to church discipline: a tolerated sin, if left unrebuked and uncensored, will spread like yeast and corrupt the entire congregation.
Jamieson-Fausset-Brown Commentary Protestant 1871
JFB emphasizes that the Corinthians' pride in their own spiritual achievements and their favorite teachers is completely inconsistent with tolerating open scandal in the church. The leaven metaphor warns that such complicity spreads guilt and risks infecting the whole community.
Lange's Commentary Reformed 1857
Lange emphasizes that the "little leaven" refers to the moral corruption of fornication tolerated in the church, not simply the incestuous individual. The old leaven is the remnant of their former unregenerate state still at work. Christians are already unleavened ideally through Christ's sacrifice, so the command to purge evil calls them to
Matthew Henry's Commentary Reformed/Presbyterian 1710
Henry notes that the Corinthians' sin was so shameful that even pagans would not speak of it, yet the church was puffed up instead of grieving. Their pride in tolerating such scandal brought reproach on the Christian name, while they should have mourned and removed the offender.
Vincent's Word Studies Evangelical 1887
Vincent distinguishes "glorying" as the condition of the Corinthians themselves, not Paul's act of boasting. He highlights "lump" as a significant word that underscores the church's unity and the shared threat posed by evildoers.
Wesley's Explanatory Notes Methodist/Wesleyan 1754
Wesley warns that boasting in gifts or prosperity is wrong when sin still lingers. He identifies the little leaven as one sin or one sinner that spreads guilt and infection through the entire congregation, making such pride dangerous.