[First.] In the thirteenth chapter of the book of Deuteronomy [Verses 1, 2, 5.] it is written: “If a prophet or a dreamer arises among you and gives you a sign” etc. “and says: Let us go after other gods and serve them,” etc., “that prophet shall be put to death, so that you purge the evil from the midst of you.”
In this decree it must be noticed first of all that it is not false faith or the mere personal confession of it that is abolished or punished but rather the teaching or preaching office, for the law does not say: Whoever believes falsely, but rather: “When a prophet says: Let us go after other gods.” So among the Jews, too, false faith went unpunished and only the teaching or preaching office of a false faith was stopped.
In the second place, it is clear that among the Jews the administration and execution of this law was assigned to the kings, i.e., to the secular government. For when the Jews chose and anointed a king, the Levites placed into his hands a copy of this book of Deuteronomy, which contains the above-mentioned law, so that he might rule his kingdom according to its teachings and statutes. [See Deuteronomy 17:18-20.]
But it is said that the Old Testament no longer binds anyone and that if one is bound by one provision, one cannot avoid being bound by the others It is true and certain that the Old Testament in and of itself no longer binds or constrains anyone. Nevertheless, as Paul testifies in 2 Tim. 3[:16], “all scripture” of the Old Testament “is given by inspiration of God, and is profitable for teaching, for reproof, for correction, and for training in righteousness,” etc. Paul himself uses many passages from the Old Testament for purposes of teaching, namely in 1 Cor. 9[:1-12], where he teaches that the apostles should be provided with food and drink and that they, the apostles, by virtue of their office, have a right to food and drink, and cites as his authority the law of Moses, Deuteronomy 25[:4]: “You shall not muzzle an ox when it treads out the grain.” Might not someone have confronted Paul and said: My dear fellow, the Old Testament binds Christians not at all, as you yourself have preached, so your text proves nothing. Paul would certainly have replied as follows: I know very well that the letter of the Old Testament binds no one, but no one can on that account forbid me to cite something from it for purposes of doctrine and instruction. He does the same thing in 2 Cor. 13[:1], where he says: “This is the third time I am coming to you; in the mouth of two or three witnesses must everything be established.” Is this regulation not taken from Deuteronomy, chapter 17[:6]? [Probably Deut. 19:15.] Thus it is indeed true that the letter of the above-cited law about putting false prophets to death no longer binds any Christian government. On the other hand, because it was the case that among the Jews the execution of this law was assigned by divine ordinance to the secular magistrate, it follows that today one may properly extract from this a lesson for the Christian magistrate concerning his office, namely that he should seek just and appropriate means to curb false and damaging doctrine and worship among his subjects. Similarly, a preacher of the truth should draw from the same passage the lesson that it also behooves him, for himself and in his own way, to confront and curb false preaching among the people of his parish. And thus we have here instruction for both offices, for the secular magistrate and the preacher, each in its own appropriate way, the secular government with its secular penalties or restraints, and the preacher with his spiritual penalties and restraints.
But again it is said: A secular government could well draw from this law [I.e., Deuteronomy 13:1-2, 5.] the lesson that it would be justified in putting a false teacher to death rather than just expelling him from office or from the territory. What would be the outcome of that? Answer: The government cannot do this; for if it were to insist on the letter of the law in this instance, then it would be bound by all the other laws of Moses, as is correctly stated in the memorandum on the basis of St. Paul in Galatians 5[:3]. To avoid error, the government must draw its lesson from the intent and purpose of this law, which is ultimately that evil and disorder should be prevented. Can a government do that with fair words? In all likelihood it will only be able to do so by means of banishment from the territory, but surely only after all convenient, godly means to curb evil and disorder have been tried by the government. If evil and disorder are and can be prevented, by whatever means, without the penalty of bodily death, then that is enough to satisfy the intent and purpose of the law.