The Bible Says
1 Corinthians 5:6-8 Meaning

In 1 Corinthians 5:6-8, Paul gives an illustration involving yeast, making the point that open immorality in the church that is not dealt with will be like a cancer that destroys the health of the body.

In the prior section, Paul admonished the Corinthian believers to expel those among them who were openly practicing immorality, specifically the case of one of the members having an affair with his father’s wife (1 Corinthians 5:1). Paul has already told the Corinthians that they are arrogant, that they have an inflated view of their own opinion, elevating it over the true substance of God’s law, which “belongs to Christ” (Colossians 2:17), He now adds to the idea of arrogance—boasting: Your boasting is not good. Do you not know that a little leaven leavens the whole lump of dough? (v.6).

The boasting here in context likely pertains to rationalizations as to why the open immorality within their body could be tolerated. The same Greek word translated here as boasting is rendered “proud confidence” in Philippians 1:26. In Philippians, Paul speaks of the Philippians’ “proud confidence” in him which would “abound in Christ Jesus.” Paul uses a form of the same word in 2 Corinthians 10:17 when he says, “But he who boasts is to boast in the Lord.”

So, boasting in the Lord is good. Having confidence in Christ is good. What is not good is having pride in self, which is arrogance. What is not good is boasting that “I know best” rather than humbling ourselves before our Creator. To claim “I know best” is to exercise confidence in our own knowledge, which has its roots in the original sin. Adam and Eve decided to pursue knowledge independent of God, which led to death (Genesis 2:17).

Boasting in self comes from confidence in self, which is arrogance and pride. Habakkuk 2:4 positions pride as the opposite of faith. Pride is confidence in self, faith is confidence in God. Righteousness comes from walking in faith that God’s ways are for our best. In Romans 1:17, Paul quotes Habakkuk 2:4 and makes the point that righteousness comes from living by faith, faith that God’s ways are for our best.

The Corinthian church is charting its own way. And, as Paul sets forth in Romans 1:18-28, this leads to severe adverse consequences. God’s “wrath” is to give people over to their own desires, removing protection with the result that they can get what they desire. Only their desires lead them to become enslaved. Lust becomes addiction becomes loss of mental health (Romans 1:26, 28, 6:16).

It is the job of the church leaders to protect the body, like a shepherd protects the sheep. And Paul makes the point that open, willful sin that is not dealt with by leadership is like leaven. Leaven is yeast. It takes only a small amount of yeast to cause bread to rise. Yeast for a loaf of bread typically makes up less than one percent of the substance of the bread’s volume. Yet this small amount causes the dough to double in size when it rises. Paul appeals to this image when he says a little leaven leavens the whole lump of dough.

In this case, the leaven refers to the immorality of a man having his father’s wife (1 Corinthians 5:1). The point is that this sinful couple might only be a small part of the assembly, but their sin affects everyone. The “culture” of any human organization is set by what is honored or even tolerated. What people within an organization have sufficient care to honor or shame reflects the values held by that organization.

Culture is typically set by informal enforcement. For example, in America there is a strong culture based on the shared value of “first come first served.” “First come first served” comes out of the value to “love others as you love yourself” or “treat others as you want to be treated.” When people cut in line, they are typically shamed for not honoring this cultural value. In many other countries, “first come first served” is not a respected value and pushing to the front of a line is expected behavior.

Applying this principle, when a church tolerates open sin, it leads to a culture of sin. Thus, sin is honored. And this encourages the entire assembly to sin. That is why Paul tells Titus to appoint elders in the church in Crete who are “able both to exhort in sound doctrine and to refute those who contradict” (Titus 1:9). If truth is valued, then it must be contended for.

In biblical symbolism, leaven often represents the pervasive influence of evil or pride (Matthew 16:6). The believer’s life, however, is to be free from "the deeds of the flesh" (Galatians 5:19). By allowing such a scandalous sin to remain unchallenged, the Corinthian church risked normalizing immorality and undercutting the purity they were called to maintain as God’s people (1 Peter 2:9).

Moreover, this verse underscores the biblical reality that each believer’s conduct affects the entire Body of Christ (1 Corinthians 12:26). Our individual decisions have corporate implications, signifying that spiritual health is not an isolated matter but one that involves and impacts everyone in the fellowship. Seeing and experiencing the church as the Body of Christ has been and continues to be difficult in the world in which we live, but necessary if we are truly to be the church (Galatians 5:24-25).

Paul is not one to complain, then not offer a solution. He instructs the Corinthians what to do: Clean out the old leaven so that you may be a new lump, just as you are in fact unleavened. For Christ our Passover also has been sacrificed (v.7).

The call to clean out the old leaven suggests a radical removal of sin and anything that fosters corruption. The image harkens back to the Passover feast in the Old Testament (Exodus 12:15) when the Israelites had to rid their homes of all leaven before celebrating. This act symbolized separating themselves from sin and dedicating themselves to God’s covenant.

Galatians 5:24 describes the reality that in Christ, believers are made new creations, and have an inner reality of this radical removal, "Now those who belong to Christ Jesus have crucified the flesh with its passions and desires." The verb translated “have crucified” is in the third person, meaning that Jesus is the one who has cleansed us of sin (Colossians 2:14). Paul now asks the church body to do for their assembly what Jesus has done for each believer: cleanse it of sin.

In the Passover ceremony only unleavened bread was to be used. The Last Supper was likely a Passover Seder, and Jesus used unleavened bread as an illustration of His body (1 Corinthians 11:23-24; see also our article, “Was Jesus’s Last Supper a Passover Seder?”) Paul connects to this new covenant imagery by declaring, For Christ our Passover also has been sacrificed. (See our article on Jesus and the Passover).

This Passover imagery underscores the present reality that believers are cleansed from sin through the sacrifice of Jesus Christ (John 1:29, 1 John 1:7, 9, Acts 15:8-9). He is the true Lamb of God that the Passover lamb foreshadows. Unlike Passover lambs who were sacrificed annually, Jesus’s sacrifice was once for all (1 Peter 3:18, Hebrews 7:27). Jesus was sacrificed for the sins of the world (John 3:16). When believers participate in communion they remember His death.

Followers of Jesus are called to live in holiness and sincerity, apart from sin. This is represented by the unleavened bread. Believers in Jesus are called to leave behind the old ways of sin (Ephesians 4:22-24).

Furthermore, just as you are in fact unleavened underlines that positionally, in Christ, believers are made holy (2 Corinthians 5:17). Yet practically, it requires a choice to live out that spiritual reality. The Spirit and flesh contend with one another within each believer, who must choose which to follow (Galatians 5:16-17).

Continuing the same thought of living apart from sin, Paul says, Therefore let us celebrate the feast, not with old leaven, nor with the leaven of malice and wickedness, but with the unleavened bread of sincerity and truth (v.8).

Paul connects celebrate the feast with Passover from verse 7 by using Therefore. Paul uses the Passover feast as a metaphor for living. There is a binary choice on how to live. Living like the leaven of malice and wickedness is like eating leavened bread at Passover, which defiles the ceremony. But living in sincerity and truth is like eating unleavened bread in the Passover, which is according to its design and consistent with God’s command for the festival.

To decide “I know better and will eat this Passover meal any way I want” would be to openly rebel against God. Similarly, living in malice and wickedness is living apart from God’s design, and therefore in open rebellion against Him. The Greek word “kakias” translated as of malice is also found elsewhere (with the same root word “kakia”), where it is rendered:

• Trouble (Matthew 6:34)
• Wickedness (Acts 8:22, James 1:21)
• Evil (Romans 1:29, 1 Corinthians 14:20, 1 Peter 2:16)

We can get a sense of the word from James 1:21 which speaks of “wickedness” (“kakia”) that is within our sinful nature. James 1:14-15 describes a progression, where our inner lusts lead to sin which brings forth death. James 1:21 urges believers to set aside “wickedness” or malice and replace it with God’s word, to deliver their lives from the adverse consequence of sin.

The Greek word translated wickedness is also found in Acts 3:26 which says that Jesus was sent to “bless” Israel by turning them away from their wicked (“kata”) ways. To walk in a leavened manner is to walk in the ways of this world, following its lusts (1 John 2:15-16). This leads to death (separation from God’s design). To walk in obedience to Christ is to live free from the power of sin.

The ancient Jewish festival of Unleavened Bread, which immediately followed the Passover, is a symbol of Jesus. Jesus was without sin, pictured by the unleavened bread. According to tradition, the unleavened bread was pierced and striped, picturing Jesus having His side pierced and receiving stripes from a whip. When we walk in the ways of Christ, we walk as He is, and He is free from sin, pictured by unleavened bread.

The old leaven is the sin and corrupting influences from the past life, including resentful attitudes or immoral behavior. Paul lists the "deeds of the flesh" that represent behaviors that flow from the old nature in Galatians 5:19-21, "immorality, impurity, sensuality, idolatry, sorcery, enmities, strife, jealousy, outbursts of anger, disputes, dissensions, factions, envying, drunkenness, and carousing." These behaviors correspond with malice and wickedness. The fruit of the Spirit listed in Galatians 5:22-23, “love, joy, peace, patience, kindness, goodness, faithfulness”—these behaviors correspond to living in sincerity and truth.

Sincerity points to being free from pretense, while truth emphasizes loyalty to God’s word. As Jesus said in John 17:17, speaking to His Father, “Your word is truth.”

The church in Corinth—and believers today—are thus called to authentically reflect Christ’s righteousness. This is possible through the empowering presence of the Holy Spirit. When we choose to follow the Spirit, we gain the power of the Spirit with a byproduct of producing the fruit of the Spirit.

The unleavened bread represents Jesus, who proclaims, "I am the bread of life; he who comes to Me will not hunger, and he who believes in Me will never thirst" (John 6:35). The fruit of the Holy Spirit produces a righteous life represented by unleavened bread.

The context of Chapter 5 is dealing with sexual immorality within the church. This section has focused on the fact that refusing to deal with such behavior within the assembly of believers spoils the entire church, like leaven spreads through dough. In modern terms we might say “a little cancer spreads until it becomes deadly.” Paul will deal further with sexual sin in the next chapter, noting that sexual sin is a sin against one’s own body (1 Corinthians 6:18). Similarly, tolerating sin within the church harms the body of Christ.

We can also note that after Paul asserts in 1 Thessalonians 4:3 that God’s will for each believer is that he be sanctified (by living in a manner that is set apart from the world), that the first behavior he says believers should stand apart from is “sexual immorality.” Sexual immorality is fundamentally exploitative as well as addictive. We cannot love someone by seeking their best (as Paul will describe in 1 Corinthians 13) while also seeking to exploit them for our own pleasure.

We can also note that in the book of Revelation, Jesus exhorts the church in Pergamum to resist immorality in their body (Revelation 2:14), as well as the church at Thyatira (Revelation 2:20). This is consistent with Paul’s message to the church at Corinth, urging the believers there to not tolerate and to distance themselves from condoning behavior that is sexually immoral.