In writing to the Christians of his day, Paul advised church members to avoid divisiveness and people who were divisive. This was Paul's habitual way of dealing with such people. He simply did not usually confront such people or command that they be cast out of the Church.
He wrote to the saints at Thessalonica: "If anyone does not obey our instruction in this letter, take special note of him. Do not ASSOCIATE with him, in order that he may feel ashamed. Yet do not regard him as an enemy, but warn him as a brother." (II Thessalonians 3:14)
He wrote to the saints at Rome: "I urge you, brothers, to watch out for those who cause divisions and put obstacles in your way that are contrary to the teaching you have learned. Keep away from them. (Romans 16:17)
Paul also wrote to Titus: "But avoid foolish controversies and genealogies and arguments and quarrels about the law, because these are unprofitable and useless. Warn a divisive person once, and then warn him a second time, After that, have nothing to do with him." (Titus 3:9-10)
Notice that in all of these instances no formal or public ceremony of marking someone or casting someone out of the Church is stated or implied. As the modern English translations and any good concordance/lexicon makes clear, the terminology used in these verses suggests that one "take note of" such divisive individuals.
What did Jesus Christ have to say about dealing with troublesome members of the flock? He said: "Moreover if thy brother shall trespass against thee, go and tell him his fault between thee and him alone: if he shall hear thee, thou hast gained thy brother, But if he will not hear thee, then take with thee one or two more, that in the mouth of two or three witnesses every word may be established. And if he shall neglect to hear them, tell it unto the church: but if he neglect to hear the church, let him be unto thee as a heathen man and a publican." (Matthew 18:15-17) How did Christ treat heathens and publicans? Did he shun them or excommunicate them?
In fact, when Christ was asked how often we should forgive a brother who sins against us, he replied "seventy times seven." (Matthew 18:21-22) Jesus then proceeded to remind his listeners in the form of a parable about how much God has forgiven us, which he indicated is much more than any of us will ever be required to forgive of each other. (Matthew 18:23-35)
Nevertheless, perhaps the clearest indication of how Christ felt about the matter was conveyed in another parable. Christ said: "The kingdom of heaven is likened unto a man which sowed good seed in his field: But while men slept, his enemy came and sowed tares
Christ clearly said that it would be a mistake to remove the "weeds" while the crop was maturing. Moreover, just so that there would be no mistaking that he was really talking about Christians within the Church, he explained the parable to his disciples. (Matthew 13:36-43)