Matthew 5:14. You are the light of the world. A city set on a hill cannot be hid.
15. Nor do men light a lamp and put it under a bushel, but on a stand, and it gives light to all in the house.
Here is the second part of the ministry which He entrusts to His dear apostles. They are to be called a “light of the world” and are to be one; that is, they are to instruct souls and guide them to eternal life. Thus He subjects the whole world to the apostles, through whom alone it should and must be enlightened; and He concludes that it, together with everything it can do, is all sheer darkness and blindness. Or if it had a light to enlighten it without this, as it supposes, why would He need the apostles for this? You see, is this not a superb and splendid ministry, an honor above every honor? All the people in the world—kings, princes, lords, learned men, wise men, holy men—have to sit down while the apostles stand up, have to let themselves be accused and condemned in their wisdom and sanctity as men who know neither doctrine nor life nor the right relation to God.
Now along comes Master Pope with his masks, the bishops. They lay claim to the title “vicegerents of Christ and of the apostles.” They have the audacity to lord it over Christ’s Word and to depose the apostles by slobbering that it was not enough for the apostles to preach and for the Holy Spirit to shine through them, but that we must hear and heed the decrees of the holy fathers, the councils, and the popes, who have taught much more and better. But we should know that Christ is not some sort of juggler who does not know what He is saying. Because He calls them a “light of the world,” their teaching alone must be authoritative and adequate to enlighten the whole world. Therefore no other light is necessary; indeed, anything apart from their teaching is sheer darkness. Others may shine far with their lanterns, but these are merely human regulations to govern certain outward affairs which everyone understands and could discover and make up for himself without their help. So the right name for them is not “light of the world” but “law of God,”22 since they are people who take it upon themselves to regulate God Himself and His Christendom with their laws, as though they were so much better than the apostles. They snuff out the light of the apostles with their blind doctrine, which cannot give proper criticism or instruction to any man’s conscience, as is evident in all the books put out by the pope and all the universities. Thus they cannot be called either “salt” or “light.” At their best they condemn the coarse, outward evils that have already been condemned by secular law and the light of reason. But they pay no attention to the truly hard knots and the main problems, like unbelief and false sanctity; in fact, they themselves are in them over their ears. Therefore their teaching is tasteless salt, as well as darkness and blindness. The highest things they can find to salt and enlighten are matters like eating meat or fish, dressing or behaving one way or another.
It is, therefore, exclusively the ministry of the apostles to condemn the real inward evil correctly, and then to heal, console, and comfort all the poor and distressed consciences, leaving no one without condemnation for his evil and instruction and encouragement for the good. Christ installs and ordains them as preachers who alone deserve to be heard, without competition from any schismatic spirits introduced by the devil. Such people want to be known as “salt” and “light.” They even lord it over Christ and scream: “The teaching of faith is a trifle! You must go far beyond that, torture yourself, suffer, and let yourself be crucified.” If you look it over from every side, this is merely instruction about our own actions, without ever pointing to unbelief or condemning the really proud vices that cling to the instruction, which they themselves elevate as “salt” and “light.” They do not stick to the calling and command which He gives to the apostles here when He says: “You shall be the light.” Our only aim is to create the confidence and the declaration that Christ has ordained and anointed us to do this salting and shining, on the basis of God’s command and our ministry.
This is necessary for another reason as well. Christ does not want this ministry to be performed in secret or only in one place, but publicly throughout the world, He indicates to them what they should expect from the world when He says: “A city set on a hill cannot be hid. Nor do men light a lamp and put it under a bushel.” That is to say: “Anyone who is supposed to be a light must be sure that he does not sneak off into a corner, but stands up publicly and fearlessly.” As we have said before, those who are called to be apostles and to shine have this tendency. They do not like to step forward, but they let themselves be scared off by threats and danger and persecution, or fooled by friendship, acceptance, popularity, and wealth. Thus they do not step forward and open their mouth, but they sneak off into a corner, hide behind a hill, and put their whistles into their pockets.23 Take our clergy, sitting in the ministry. They have the command to stand up before Christendom and to shine publicly with their teaching. Instead, they hide it under a bench. In fact, they do even worse, for these are the very people who persecute the Word and try to extinguish the light by egging on emperors, kings, and the whole world against it. Meanwhile they sit in the house and want to be the only ones who govern the church, to control pulpit, Baptism, Sacrament, and everything that pertains to the calling and the ministry. This is what the apostles predicted: that shepherds would become wolves (Acts 20:29) and that the Antichrist would “take his seat in the temple of God and exalt himself against everything called God.” (2 Thess. 2:4).
On the other hand, there are the schismatic spirits. They have no calling to the ministry, and they would do well to stay home in the corner. Instead, they push themselves in everywhere and try to be the only ones that shine, with everyone listening to them and watching them. All they really want is to be famous, and they preach only so long as they have a following and need fear no danger. But just make them stand up like real preachers, who have been commissioned for the ministry and keep on shining in public without letting wind and weather frighten or silence or extinguish them. Then they would soon make themselves scarce, and you would not find anyone at home. So the dear office of the ministry must get it from both sides. Either those who should perform it neglect it, or those who have not been commissioned for it want to perform it. Thus it never gets the attention it deserves except when Christ grants it the kind of people whom He is describing here and whom He has already prepared, as we heard earlier.
This is what He intends to say now: “If you want, to be My preachers, you really have to be ready to take your place publicly and to stand up before the world as though you were on a high mountain. You have to be willing to be seen and heard openly, holding nothing back that you ought to preach nor hiding it under a bench. Your love for a particular person dare not cause you to keep quiet or to speak out. But since you are the light, you must shine freely and publicly without regard to honor or shame, riches or poverty, disfavor or popularity, death or life. And you must know that you are serving Me, Me who appointed you to be the light.” Those are the people He needs, people who will not let themselves be bent either to the right side or to the left. As Psalm 45:6, 7 says about the office of the ministry: “Your royal scepter is a scepter of equity; you love righteousness and hate wickedness.” That is the virtue and the glory of the Gospel and of its preachers. No other teaching is so dangerous. They all preach what people enjoy hearing and what reason can accept; they do not have to be afraid that someone will persecute them. But this teaching meets universal opposition, because its intention is to step forward and to show up the worthlessness of the world’s light and teaching. Therefore the world tries in all sorts of ways to extinguish this light or to shove it over into a corner or to put it under a bushel. It wants us to forget about our doctrine or to recant and let ourselves be twisted and turned the way it chooses. But we will not let ourselves be driven from our stand this way. We will remain as a city on a hill, a light on a candlestick in the house. Surely He who has made us the light will also preserve us as the light. Therefore He now concludes:
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 (21:61). Saint Louis: Concordia Publishing House.