Matthew 5:21 (Luther)

MATTHEW 5:21. You have heard that it was said to the men of old, “You shall not kill; and whoever kills shall be liable to judgment.”

Here He begins the correct explanation of several of the Ten Commandments, and He shows that all the Pharisees and scribes did in teaching, explaining, and interpreting them was to take the words as they stood and to apply them merely to coarse outward deeds. In the Fifth Commandment, to give one example, all they saw was the word “kill,” which they took to mean “strike dead with the hand.” This was all they taught people, as though this commandment forbade nothing beyond this. Thus they gave themselves a magnificent way out: they would not be guilty of murder if they handed someone over to another person to be killed. When they delivered Christ to the Gentile Pilate, they did not want to defile their hands with blood and wanted to stay pure and holy. They even refused to go into the judge’s house (John 18:28), and yet it was they alone who were bringing on His death and compelling Pilate against his will to kill Him. They pretended to be completely pure and innocent, and they even objected to the apostles (Acts 5:28): “You intend to bring this man’s blood upon us.” It is as though they were to say: “It was not we but the Gentiles who killed Him.” So the story is told in 1 Samuel 18:17 that King Saul did not like David and would have liked to kill him; but since he wanted to be holy, he decided not to kill him himself, but to send him among the Philistines to be killed there, so that his hand would remain innocent.
Look at this beautiful Pharisaic holiness! It can purify itself and stay pious as long as it does not kill with its own hand, though its heart may be crammed full of anger, hate, and envy, of hidden and evil schemes of murder, and though its tongue may be loaded with curses and blasphemies. That is the kind of holiness our papists have. They have become past masters at this business. To keep their holiness from being condemned and themselves from being bound by Christ’s Word, they have generously helped Him by deducing twelve counsels from His Word. These Christ did not command as necessary, but left them up to the free choice of each individual, to observe them as good advice if he wants to merit something more special than other people. It is a completely superfluous and dispensable bit of instruction.
If you ask them what their reasons are for deducing these counsels from Christ’s Word or how they prove them, they say: “Why if this were to be taught as it stands, that would impose too heavy a burden on Christian people.” That is exactly what the theologians at Paris have written against me publicly and impudently.27 A lovely reason indeed! It is a heavy burden for a Christian to be friendly to his neighbor and not to let him suffer need, to treat him the way everyone wants to be treated. Because it seems to them to be too much of a burden, they have to say that it was not commanded, but left to everyone’s free choice to do or not as he pleases, without burdening the man who cannot or will not do it. That is the way to reach into Christ’s mouth, to lord it over His Word, and to make it mean anything you please. But He will not let Himself be fooled this way, nor will He cancel the judgment that He has pronounced here when He says: “Whoever does not have a better piety, will be shut out of heaven and damned.” Or, as follows later: “A man shall be liable to the hell of fire if he says to his brother, ‘You fool.’ ” From this it is easy to figure out whether this was recommended or commanded.
They have also found a little gloss to support their lies. They say: “It is indeed a command that we should hold back anger and rancor in our heart, but not the signs of anger.” That is what we call in German “to forgive but not to forget,” to plan that you will not get angry nor do anything wrong, but that you will deny your neighbor any kindness and show him not a single good word or marks of friendship. Now ask God Himself and Christ why He did not deny His kindness to those who were crucifying Him, blaspheming Him, and shamefully ridiculing Him, but prayed for them and said (Luke 23:34): “Father, forgive them; for they know not what they do.” They were the most despicable kind of scoundrels, and He could well have been angry with them and punished them. If He had wanted to be angry with us, His blasphemous and idolatrous enemies, He would not have shed His blood for us and died for us, but would have stayed up there in heaven and said, in keeping with this gloss: “I will forgive, but I will not forget.” We would all have remained the devil’s property, and no man could have escaped hell. In short, this is an abominable and damnable gloss, and it is a sin and a shame that anyone in Christendom should have the effrontery to teach something like this, in opposition to such a clear and obvious text. They have smeared up all their books with these lies, and now they are making an impudent effort to defend them. This is to help us to see and recognize Pharisees and hypocrites, as Christ describes them here and elsewhere. With their special works they make a show of their great sanctity, but they show no hesitation in transgressing the commandments of God and teaching others to do the same.
Anger is indeed necessary sometimes, but only in those whose responsibility it is, and only if it does not go beyond the punishment of sin and evil. Thus when you see another man sinning and you warn and urge him to stop it, such anger is Christian and brotherly, yes, even fatherly. You see pious parents punishing their children, not in order to hurt or harm them, but to keep them from mischief and evil. That is also the way the government must be angry. Here it applies that there should be no anger in the heart, and yet there must be signs and marks of anger; for the voice is sharp, and the fist is rough, but the heart remains sweet and friendly, free of any malice. In other words, it is an anger of love, one that wishes no one any evil, one that is friendly to the person but hostile to the sin, as everyone can learn even from nature. But it is not right to use this as a screen for hiding and decorating the malice and envy of our heart against our neighbor, the way these sanctimonious scoundrels do and teach.
Now, in considering this commandment, Christ wants to say: “You have heard from the Pharisees that Moses commanded and that of old it was taught (Ex. 20:13): ‘You shall not kill.’ You use this to flatter and decorate yourselves, acting as though you faithfully taught and obeyed the laws of God which Moses taught and which the men of old received. You stand up and insist: ‘Here is Moses. He says, “You shall not kill.” ’ You are stuck on that word, and you refuse to allow any interpretation beyond the way it sounds in its coarsest sense. Thus simple-minded people have to say: ‘So it is. That is the way it reads in the book.’ Thus your constant harping and your worthless glosses obscure the words and make it impossible to see what they contain and mean.” Do you suppose that He is talking only about the fist when He says: “You shall not kill”? What does the word “you” mean? Not just your hand or foot or tongue or any other organ, but everything you are in body and soul. When I say to someone, “You should not do that,” I am not addressing only his fist but his total person. Even if I were to say, “Your fist should not do this,” I would not mean just the hand but the total person to whom the hand belongs; for the hand would do nothing by itself if the whole body with all its organs did not co-operate.
“You shall not kill,” therefore, is equivalent to saying: “You may find as many ways to kill as you have organs. You may use your hand, your tongue, your heart; you may use signs and gestures; you may use your eyes to look at someone sourly or to begrudge him his life; you may even use your ears if you do not like to hear him mentioned.—All this is included in ‘killing.’ Your heart and everything about you would be happy if he were already dead. Meanwhile your hand may be still, your tongue quiet, your eyes and ears muffled. Still your heart is full of murder and homicide.”
Luther, M. (1999, c1956). Vol. 21: Luther's works, vol. 21 : The Sermon on the Mount and the Magnificat (J. J. Pelikan, H. C. Oswald & H. T. Lehmann, Ed.). Luther's Works (21:74). Saint Louis: Concordia Publishing House.