Far from being an ecumenical, open-arms type with anyone who professes to have eternal life, the Apostle Paul revealed God’s strict call to holiness, essential to the Christian faith:
But now I am writing you that you must not associate with anyone who calls himself a brother but is sexually immoral or greedy, an idolater or a slanderer, a drunkard or a swindler. With such a man do not even eat. (1 Cor 5:11)
It would be a sin for the Corinthian Christians to associate with any professing Christian who negated his own profession of faith by his unholy behavior. The unholy behavior mentioned is later repeated in 1 Cor.6: 9,10 and there we are also told not to be deceived— that such people will not inherit God’s kingdom!
Unholy behavior from a professing Christian is noteworthy! It not only reveals that such a person (a child of the devil) is not saved at the moment, it also means that real Christians must not associate with him for his sake! Not associating with a backslider, who lost his salvation, or a false convert will help bring about repentance and salvation. To continue to associate with an unholy person who professes salvation would nullify that advantage plus endanger the Christian body. To “look the other way” and consider the professing Christian saved is to say there are Christian fornicators, Christian greedy people, Christian idolaters, Christian slanderers, Christian drunks, Christian swindlers, which would spread more sin. Though the concept of Christian adulterers, Christian slanderers, Christian drunks is common in our apostate day through Calvinism, such is clearly foreign to the image of a Christian revealed in Scripture.
Finally, 1 Cor. 5:11 is a devastating view to the merciless smear campaign the grace changers have done to the Corinthians, by teaching they were carnal meaning they were sexually immoral, drunks, etc. Why? Because it is obvious that the Corinthians were not described in the 1 Cor. 5:11 list of people they were to not associate with! They could not have been committing the same sins others were committing whom they were told to stay away from. Some so-called holiness preachers of our day violate 1 Cor. 5:11 by co-laboring with slanderers, and such, as though it was nothing, and reveal their own immorality by doing so. Remember:
Make every effort to live in peace with all men and to be holy; without holiness no one will see the Lord. (Heb 12:14)