Situations frequently happen in churches where unrepentant sin begins to affect the church as a whole. It only takes a little leaven to “leaven the whole lump.” But what should the church do? Immediately we might say, ” Judge not!” But is that the biblical response? Is there such a thing as a  “biblical response”? If there is, can we follow that today?
The two most well-known biblical texts that speak about the issue of unrepentant sin in the church are Matthew 18:15-20 and 1 Corinthians 5. In the Gospel of Matthew, Jesus teaches that if a brother or sister is in unrepentant sin and refuses to listen, finally to the church, then they are to be treated ”as a Gentile and a tax collector.” In 1 Corinthians 5, a man was involved in scandalous sin and Paul instructs the church ”to deliver this man to Satan for the destruction of the flesh, so that his spirit may be saved in the day of the Lord” (verse 5). Then he states in verse 11, “‘But now I am writing to you not to associate with anyone who bears the name of brother if he is guilty of sexual immorality or greed, or is an idolater, reviler, drunkard, or swindler—not even to eat with such a one.”
There are other passages that could be used to support the idea that the church is to be a group of believers who seek to follow the Lord. The church obviously is not sinless or without struggles with sin. But it seems that the church is to be holy (1 Peter 1:16). The biblical mandate is clear. the church is not to tolerate unrepentant sin among its members.
There have been times when a pastor has had to address the problem of unrepentant sin among one of the members. If the church does not have any form of church discipline in its constitution or bylaws, the pastor can really do nothing. The pastor can warn the individual, but the individual can simply ignore the pastor. He or she may even get the support of the church against the pastor. If the church refuses to repent and deal with the unrepentant sin then what is to be expected?
When John has his vision of the resurrected Lord Christ in the Book of Revelation, notice what the Lord said to the church at Ephesus: “Remember therefore from where you have fallen; repent, and do the works you did at first. If not, I will come to you and remove your lampstand from its place, unless you repent (2:5). Jesus threatens to remove his presence from the church. And any church that ignores unrepentant sin among its members should expect nothing less than the loss of the presence of the Lord. I am afraid this is widespread in our day.
All of this talk of discipline can sound harsh and unloving. Nevertheless it is a biblical concept and one that is good for the believer as well. Paul told the Corinthians that the man was to be delivered over to Satan so that his soul might be saved. The turning over to Satan was only for the destruction of the flesh. Ultimately, Paul wanted the unrepentant member to repent and be saved. The goal is always restorative and never punitive. Of course church discipline has been abused, but the real question is, ”Is it biblical?” If it is, how should we go about it? Let us imitate Jesus in this way. He was kind and merciful to “’sinners.” But to the hypocrites he was harsh and straightforward. If the church knowingly tolerates unrepentant sin, it is no more a church of believers. James 4:17 says that the one who knows the right thing to do and fails to do it, to him it is sin.