Titus 3:10

There will be those within the church that causes trouble. With regards to these people, Titus is instructed by Paul to deal with this and warn them. However, you cannot continue warning them if they continue to ignore you and cause trouble. Therefore, Paul instructs that after warning them twice you should have nothing to do with them. This sounds similar to Jesus' instruction to show a brother his fault when he sins against you. The end of the matter is either winning your brother over, or treating him as a pagan or tax collector.