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.
Many who do not understand Christ’s will for us ask whether a Christian may or should use the sword against the wicked for the protection and defence of the good, or for the sake of love.
The answer is unanimously revealed: Christ commands us to learn from Him, for He is meek and lowly of heart so we may find rest for our souls. Christ did not say the woman who was taken in adultery should be stoned according to the law of His Father (and yet He says, “What the Father commanded me, that I do”) but with mercy and forgiveness and the warning to sin no more, he said: “Go, sin no more.” We should do exactly that, with the rule of the ban.
People also ask whether a Christian should pass sentence in disputes and strife about worldly matters, like the unbelievers. This is the answer: Christ did not wish to decide or pass judgement between two brothers concerning their inheritance. He refused to do it and we should also refuse.
A third question people ask is whether Christians should become magistrates or take civil office if they are elected to one. This is the answer: When they tried to make Christ a king he fled, even though he had access to all power and authority in heaven and on earth. We should do as he did and follow him, not walking in darkness. For Christ says: “Whoever would come after me, let him deny himself and take up his cross and follow me.” Christ forbids the violence of the sword when He says: “The princes of this world lord it over them, etc., but among you it shall not be so.” Further Paul says, “Whom God has foreknown, the same he has also predestined to be conformed to the image of his Son.” Peter also says: “Christ has suffered (not ruled) and has left us an example, that you should follow after in his steps.”
Finally, one can see in the following points that it does not befit a Christian to be a magistrate: the rule of the government is according to the flesh, that of the Christians according to the Spirit. Their houses and dwelling remain in this world, that of the Christians is in heaven. Their citizenship is in this world, that of the Christians is in heaven. The weapons of their battle and warfare are carnal and only against the flesh, but the weapons of Christians are spiritual, against the fortifications of the devil. The worldly are armed with steel and iron, but Christians are armed with the armour of God, with truth, righteousness, peace, faith, salvation, and with the Word of God.
As Christ our Head is minded, so we (the members of his body) must also be minded, so that there is no division in the body, through which it would be destroyed. Since Christ is as was written about him, his members must be the same way, so his body may remain whole and unified for its own advancement and upbuilding. For any kingdom divided against itself will be destroyed.
Read the entire Brotherly Agreement of Schleitheim.