Matthew 18:17
And if he refuses to listen to them [i.e., the witnesses], explain the [whole] matter to the church [i.e., probably a specially called meeting of mature Christians to resolve the matter]. And if he refuses to listen to the church also, [i.e., to acknowledge his sin and repent of it], consider him like an [unconverted] Gentile or tax collector [i.e., do not have fellowship with him].
John 9:22
His parents said these things because they were afraid of the Jewish authorities who had already decided that anyone who confessed Jesus to be the Christ would be expelled from the synagogue.
John 9:34
They replied to the beggar, "You were born entirely in sins [i.e., you have been a sinner all your life], and you are [trying] to teach us?" Then they threw him out [of the synagogue. See verse 22].
John 16:2
The Jewish authorities will expel you from their synagogues. In fact, the time will come when whoever kills you will think he is doing a service to God.
1 Corinthians 5:13
For what business is it of mine to judge outsiders? [i.e., non-Christians]; God judges them. But should you not judge those people who are inside? [i.e., Christians]. [So], remove the evil person from your fellowship [See Deut. 17:7].