An extended reading of Walther…
Among the various functions and official acts of a servant of the Church the most important of all, my friends, is preaching. Since there is no substitute for preaching, a minister who accomplishes little or nothing by preaching will accomplish little or nothing by anything else that he may do.
Here is where the papists differ with us. They call their ministers priests and assert that the most important of all functions of a priest is to baptize, hear confession and pronounce absolution, administer Communion, and, above all, to offer to God the sacrifice of the Mass. Setting aside the sacrifice of the Mass, which is the greatest abomination that has ever been practised in the Christian Church, we are forced to say that all baptizing, pronouncing absolution and administering of Communion is useless if these matters have not been previously made the subjects of preaching to the people; for they are not the works of men, but of God Himself, who has connected with them a promise to be apprehended by faith. Accordingly, all these acts do not profit, but are rather harmful, in the absence of faith. If these operations of God are to be of any use, it is absolutely necessary that a thorough instruction concerning them be first given from the Word of God by preaching.
This function, however, is not only the most important, but also the most difficult function assigned to a minister of the Church. There are ministers who imagine that preaching is easy to them, and the longer they are in the ministry, the easier preaching becomes to them; for they reason that, if they are only careful to preach nothing but the pure Word of God, without any admix ure of heresy, that must be sufficient. Such preachers are laboring under a great, an awful, a very pernicious error. A mere pious talk without aim and logical order is not real preaching. Genuine preaching is inspired only by the Holy Ghost through His Word. Accordingly, a real sermon is produced only after all the spiritual and intellectual energy of a truly believing preacher has been exerted to the utmost, after fervent prayer, after all earthly cares have been chased from the mind, and after the preacher has been freed from all vain desires. That is a difficult task.
What is to be effected by preaching? Bear in mind that the preacher is to arouse secure souls from their sleep in sin; next, to lead those who have been aroused to faith; next, to give believers assurance of their state of grace and salvation; next, to lead those who have become assured of this to sanctification of their lives; and lastly, to confirm the sanctified and to keep them in their holy and blessed state unto the end. What a task!
A preeminent point that we must not forget is this: To achieve this task, it is especially necessary rightly to divide the truth, as the apostle says, or properly to divide the Law and the Gospel from each other. When a person does not understand how to do this and always mingles either doctrine into the other, his preaching is utterly futile, in vain. More than this, a preacher of this kind does harm and leads the souls of men astray; he leads them to a false faith, a false hope, a false contrition, makes them mere hypocrites, and frequently hurls them into despair. To divide Law and Gospel properly is a very, very difficult task. As Luther says, all preachers cannot but remain mere apprentices in this art until death. Nevertheless, a young theologian must be able to recite at least the first lesson in this curriculum. He must know the goal that he is to reach, and he must have made a start in reaching the goal.
- from C.F.W. Walther, 'Law and Gospel, Twenty-third Evening Lecture' (March 20, 1885.)