1 Corinthians 5:9-10

5:9 I wrote you in my letter not to associate with sexually immoral people. 5:10 In no way did I mean the immoral people of this world, or the greedy and swindlers and idolaters, since you would then have to go out of the world.

1 Corinthians 5:12

5:12 For what do I have to do with judging those outside? Are you not to judge those inside?