You keep saying things that are not in the bible or cannot be clearly proven by what is given. Show me in the bible.
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 a drunkard, or an extortioner; with such an one no not to eat. (1 Corinthians 5:11)
--He was called a brother (in Christ), and so he was. He was to be treated as one.
For what have I to do to judge them also that are without? do not ye judge them that are within? (1 Corinthians 5:12)
--Do you exercise discipline on all the unsaved fornicators? You would be awful busy wouldn't you? This man was a brother, a member of the church. He was saved.
So that contrariwise ye ought rather to forgive him, and comfort him, lest perhaps such a one should be swallowed up with overmuch sorrow. (2 Corinthians 2:7)
--He had repented. But it was hard to receive such a one back into the fellowship. That is human nature. When someone causes a scandal in the church the church members are reluctant to receive that one whom they have disfellowshipp back in. This is what Paul is urging them to do. Forgive him. God has. He has repented. If you don't take him back "such a one would be swallowed up with too much sorrow."
He was a brother in the Lord who had repented from his sin.
Any Christian can sin. They are capable (like David) of heinous sin, if their walk is not right with the Lord. If that be the case they need to be restored back to fellowship.
The entire book of Hebrews is written to backslidden Jewish Christians who needed to be restored to the Lord. Hebrews 12 especially is a key chapter here. Why would Paul spend most of chapter on the chastening of his children if they didn't go astray?