1 Corinthians 5:6-8
6-8Your flip and callous arrogance in these things bothers me. You pass it off as a small thing, but it's anything but that. Yeast, too, is a "small thing," but it works its way through a whole batch of bread dough pretty fast. So get rid of this "yeast." Our true identity is flat and plain, not puffed up with the wrong kind of ingredient. The Messiah, our Passover Lamb, has already been sacrificed for the Passover meal, and we are the Unraised Bread part of the Feast. So let's live out our part in the Feast, not as raised bread swollen with the yeast of evil, but as flat bread—simple, genuine, unpretentious.
9-13I wrote you in my earlier letter that you shouldn't make yourselves at home among the sexually promiscuous. I didn't mean that you should have nothing at all to do with outsiders of that sort. Or with crooks, whether blue or white-collar. Or with spiritual phonies, for that matter. You'd have to leave the world entirely to do that! But I am saying that you shouldn't act as if everything is just fine when a friend who claims to be a Christian is promiscuous or crooked, is flip with God or rude to friends, gets drunk or becomes greedy and predatory. You can't just go along with this, treating it as acceptable behavior. I'm not responsible for what the outsiders do, but don't we have some responsibility for those within our community of believers? God decides on the outsiders, but we need to decide when our brothers and sisters are out of line and, if necessary, clean house.