1 Corinthians 5:9-13 (New American Standard Bible)
9I wrote you in my letter (A)not to associate with immoral people;
10I did not at all mean with the immoral people of this world, or with the covetous and swindlers, or with (B)idolaters, for then you would have to go out of the world.
11But actually, I wrote to you not to associate with any so-called (C)brother if he is an immoral person, or covetous, or (D)an idolater, or a reviler, or a drunkard, or a swindler--not even to eat with such a one.
13But those who are outside, God judges. (G)REMOVE THE WICKED MAN FROM AMONG YOURSELVES.
Here is my response
Mat 18:15 "If your brother sins against you, go and tell him his fault, between you and him alone. If he listens to you, you have gained your brother.
Mat 18:16 But if he does not listen, take one or two others along with you, that every charge may be established by the evidence of two or three witnesses.
Mat 18:17 If he refuses to listen to them, tell it to the church. And if he refuses to listen even to the church, let him be to you as a Gentile and a tax collector.