How do we know church excommunication is necessary?

Excommunication, or the act of withdrawing from a disorderly brother, is warranted when a member's behavior continually harms the church's integrity and fails to align with the teachings of Christ. According to Paul's letter to the Thessalonians, it is not merely about a single incident but rather an ongoing pattern of behavior that remains unrepentant despite admonition. This act is a serious step taken by the whole assembly of believers and is done under apostolic authority in the hope that it will lead the individual to recognize their sin, repent, and be restored to fellowship. The intent is always geared towards healing and correction, not condemnation.