Cleanse Out The Old Leaven



In recent times, we’ve all been very concerned about the spread of the coronavirus. But we should be even more concerned about the spread of sin. The Bible likens sin to leaven that spreads (Lk 12:1). Just a little bit of leaven has the potential to spoil a whole batch of dough (Gal 5:9; 1 Cor 5:6).

For this reason, the Apostle Paul writes to the church in Corinth: “ Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our Passover lamb, has been sacrificed ” (1 Cor 5:7). Let’s consider this eternal truth so that we can apply it both corporately and individually.


As you know, we had to “cleanse out the old leaven” a few times in the past when we had to remove members from our church who continued in unrepentant sin. These were painful times for us—full of many tears and much pain. But we had to recognize that someone who had been part of our church body no longer gave clear evidence of being a Christian. As Paul writes, the church really is unleavened. If leaven is found in the church, it needs to be removed before it starts permeating the whole “batch of dough,” the church. I’m grateful that we did have the courage to do what God’s Word commanded.

Ultimately, cleansing out the old leaven is an act of love for all parties involved.

It’s an act of love for the unbelievers who observe our church. By not accepting unrepentant sin in our midst, we showed ourselves as those who have indeed been called out of this world and made new in Christ.

It was also an act of love toward God, as we displayed a willingness to obey his Word even when it’s painful. As Christ’s body, we represent him, so allowing unrepentant sin would lie about his holiness.

It was also an act of love for the church at large. Acting otherwise would have allowed sin room to spread. This would have perhaps especially tempted younger Christians who may be deceived about sin and its destructive effects.

Finally, it was a display of love for the former member whom we disciplined. Why? Because we refused to let him or her be deceived over his or her own spiritual state. Every act of discipline ought to be done with the hope that it will lead to repentance and restoration: “that his spirit may be saved in the day of the Lord.” (1 Cor 5:5). Indeed, as I write this, I recall how our Good Shepherd has used this tool to bring two formerly disciplined members back into our flock.

In all of this, we understand that “the leaven” we are removing are not necessarily people, but sin itself. Which helps us to see how the call to “cleanse out the old leaven” can also be applied to each of us individually.


Dear brothers and sisters, if we are committed to root out sin corporately, we should also be committed to do this personally. The Bible calls us to pursue holiness and to fight sin (1 Thess 4:7); to be holy, as our God is holy (1 Pet 1:15). Indeed, Christians are holy. So let us be what we are. This is what Paul is calling us to when he writes: “Cleanse out the old leaven that you may be a new lump, as you really are unleavened.”

Let’s never assume that we can harbor a particular sin without it spreading—it will! Let’s just look at a few examples. Pornography seems to many men as a small, rather harmless sin. But it won’t take long until this leads to lies, and it promotes lustful thoughts that might lead to action. Or think about gossip. It seems like just a small comment about someone else. But once it spreads, it harms relationships. It promotes mistrust and leads to division in the church.

Therefore, we should be committed to cleansing out the leaven in our lives. Ultimately, we do this to honor our Lord who gave himself for us. That’s precisely Paul’s point: “Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our Passover lamb, has been sacrificed.”

While this should motivate us to strive after holiness, it also encourages us when we fail. Because Christ, our Passover lamb, has been sacrificed, we can be assured of God’s grace. Christ alone was free of any leaven—he was pure, blameless, and holy. And he took our sin so that we can stand before God even as we are still impure. And in him we have the power to battle sin until one day we will be transformed into his likeness.

So brothers and sisters, let’s cleanse out the old leaven of sin both corporately through corrective church discipline and individually as we fight by grace the sin in our own lives.

Matthias Lohmann

Matthias Lohmann is the pastor of an evangelical church in downtown Munich, Germany, and one of the leaders of the German gospel partnership Evangelium21.

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