We have been united as follows concerning the sword. The sword is an ordering of God outside the perfection of Christ. It punishes and kills the wicked and guards and protects the good. In the law the sword is established over the wicked for punishment and for death and the secular rulers are established to wield the same.
But within the perfection of Christ only the ban is used for the admonition and exclusion of the one who has sinned, without the death of the flesh, simply the warning and the command to sin no more.