Excommunication (Part II)

In examining the Scriptural evidence on the subject, it is essential that we remind ourselves about what constitutes the Church and who has authority over it. The English word "church" is a translation of the Greek word "ek-clay-see-ah." Strong's Exhaustive Concordance of The Bible informs us that this refers to a gathering/assembly of people who have been called out of their homes to meet together. When referring to a Christian Church, the term can indicate: 1) any gathering of Christians for worship, 2) a group of Christians, 3) the people who constitute such a group, 4) all of the saints scattered around the earth, and 5) those faithful Christians who have already died. Hence, the sense of the original Greek word tells us a lot about the nature of the Church (it is not a building, religious service, organization or denomination).
Moreover, we are told repeatedly in the New Testament that it is God who puts people into His Church. (John 6:44 and I Corinthians 12:18). Likewise, we are informed that Jesus Christ himself is the head and Supreme Authority over the Church. (Ephesians 1:22-23) Indeed, Jesus told his disciples that he would build "my" church. (Matthew 16:18) Christ specifically instructed his followers not to imitate the Gentile style of leadership by lording it over each other. (Matthew 20:25-27)
What about Paul and the saints at Corinth? Let's examine the situation in more detail. Apparently, Paul had received a report that the Corinthian Christians were tolerating an affair between a man and his step-mother. (I Corinthians 5:1) Indeed, it appeared that they were proud of their behavior instead of being repentant and grieved over what had happened. (verse 2) As a consequence the Apostle told them "to deliver such an one unto Satan." (verse5) He went on to compare their rejoicing over their tolerance of this individual to removing leavening from their houses prior to the Feast of Unleavened Bread. (verses 6-8) He concluded: "I wrote unto you in an epistle not to company with fornicators : Yet not altogether with the fornicators of this world, or with the covetous, or extortioners, or with idolaters; for then must ye needs go out of the world. But now I have written unto you not to keep company, if any man that is called a brother be a fornicator, or covetous, or an idolater, or a railer, or drunkard, or an extortioner; with such an one no not to eat." (verses 9-11)
In other words, Paul told them that their tolerance of this individual had compromised their own integrity and had contaminated the whole congregation by doing so! Paul was worried about the entire Corinthian Church being corrupted by this affair. Hence, he moved quickly to eradicate the behavior and separate the congregation from the one who was causing the offense. (verse13) So this was a very serious and unique event that was being talked about in this epistle - it was not meant to be a general instruction to the Church as a whole as to how to handle difficult members of their congregation. This is underscored by the fact that Paul reversed his stance in his follow up letter to these people. (II Corinthians 2:7-8)
We would also do well to remind ourselves here that we are discussing an apostle of Jesus Christ and the author of half of the New Testament (Paul). Who in the Church has that kind of authority and prestige today? In particular, who within the Church has the authority to impose such a punishment on one of his/her brothers and sisters in Christ?
Nevertheless, didn't Christ tell his disciples that he would support any decisions that they might make regarding the governance of his church? (Matthew 16:19 and 18:18) Does that mean that Church leaders have the authority to make decisions that God will honor in all circumstances, even if they go against one of His core principles?