But you may say: “How can He say that the Law and the Prophets consist in this? Do not the Scriptures of the Law and the Prophets contain much more than this? They contain the doctrine of faith and promises, which are not mentioned here.” The answer is that here Christ names the Law and the Prophets in direct contrast to the Gospel or the promise. He is not preaching here about the sublime doctrine of faith in Christ but only about good works. These are two distinctive proclamations; both must be preached, but each at its appropriate time. You can tell that plainly from the words in the text where He says: “Whatever you wish that men would do to you, do so to them.” By this He indicates that His preaching here does not go beyond the relation that people have with us and we with them, and that it is not talking about the grace of Christ which we receive from God. What He intends to say now is this: “When the time comes to preach about the good life and about the works which we should perform in our relations with our neighbor, you will find nothing in all the Law and the Prophets except what this saying teaches.” He uses the words “men” and “do so to them” to specify that He is discussing only the commandments of the Second Table. (Luther’s Works, v. 21, pages 239-240).

Oh, how many fellows like this there are in all the businesses and trades! They go along, smugly deceiving and cheating the people wherever they can; still they refuse to be called thieves and villains, so long as they do it secretly and adroitly. If everyone had to give back what he has stolen and robbed in his business or job, very few people would be able to keep anything. Yet they go along like pious people, because no one dares to accuse and denounce them publicly. They suppose that they are sinless; yet if they look around, every corner of their house and home is full of theft and, by God, they do not have a single gulden or two in the house that was not stolen. Yet none of this is supposed to be called theft. If it were merely theft, and not murder in addition! Shoddy merchandise or unwholesome food and drink can make people weak and sick. Thus you deprive them not only of their money but also of their health. Many a person eats and drinks and then gets sick and often dies as a result. My friend, except for the name, is this not as bad as breaking into his house or rifling his treasure chest or striking him dead?

Now, if you were not such a heinous and brazen person, you would be ashamed when your conscience says this to you and reminds you of this saying. It would give you pause. In fact, it would make you so afraid that you would be unable to remain at rest anywhere on account of it. This burden continually oppresses us and drives us. It is an eternal witness against us, always condemning us, so that it becomes unbearable. It would soon teach you that you have to stop this robbing and stealing and whatever else you would not like to have someone else do to you. Get used to looking at this saying once in a while and practicing it on yourself. Thus in your whole existence, in every task in which you have contact and dealings with your neighbor, you have a daily sermon in your heart. From it you can easily learn to understand all the commandments and the whole Law, how to control and conduct yourself personally and socially. On this basis you can easily decide what is right and wrong in the world. (Luther’s Works, v. 21, pages 239).

Those who want to be pious, who fear God, and who think about how to live and behave, must know that they simply have no right to do business with their property and manage it as they please, as though they themselves were the lords of all. They have the obligation to carry on their business in a proper and orderly way; this is why there is territorial and civil law. That is how everyone would want his neighbor to treat him; therefore he should also treat his neighbor that way, taking and offering only good merchandise. Christ means this commandment seriously, and He will not let it be made free or optional, as though one could obey it or disobey it with impunity. He will enforce it, too, however much the world may take it as an insult and despise it. If you do not obey it, He will deal with you according to your own standard and judgment, and it will strike you in your house and home. You will have no blessing from what you have acquired in disobedience to this teaching, but you and your children will have only trouble and sorrow. He wants His commandment to be kept; otherwise you will have neither property nor good fortune.

In the second place, Christ not only makes this so intimate, as we have said, that we have to see it in everything we look at, He also portrays it in such a way that everyone has to blush in shame over himself. There is no one who enjoys doing something wrong when other people can see it. No one dares to sin publicly, in the presence of people, with the same freedom as he does privately, where no one can see him. So Christ intends here to appoint us as our own witnesses and to make us afraid of ourselves. Then if we do something wrong, our conscience will stand up against us with this commandment, as an eternal witness, and say: “Look here, what are you doing? According to the usual fair-business practice, you ought to put such and such a price on this. But you are putting on a much higher price. Or the way you are debasing and misrepresenting this merchandise, you would not want to have someone else sell you something like that.” How it would annoy you if someone charged you a gulden for something barely worth ten groschen! If you had one drop of honest blood in your body, you would have to be ashamed of yourself. If someone else acted this way, you would call him a thief and a villain. Then why are you not ashamed of yourself, since it is not someone else but yourself who has to make this accusation, and you are condemned by your own conscience? This may be all right for a brazen hardhead, who has no sense of shame before the people or before himself, much less before God. But when someone else treats you that way you can quickly exclaim: “Is it not a sin and a shame and a clever¹⁸ way of robbing my wallet?” You can quickly recognize a thief and a villain in someone else; but you refuse to see the one working in your own breast, whom you can easily catch and feel. (Luther’s Works, v. 21, pages 237-239).