A first answer is found in the Canons of Dort, 2.5. “Th[e] promise [of the gospel] ought to be announced and proclaimed universally and without discrimination to all peoples and to all men, to whom God in his good pleasure sends the gospel, together with the command to repent and believe.” According to this article, the address of the gospel is universal: everyone must hear the same message. The content of the preaching is primarily “promise”, in the sense of presenting the listener with the certain reality of salvation in Christ. (See Trimp, Klank en Weerklank, 58.) This promise, this indicative of God’s grace for the recipient, must be accompanied by the imperative, the commanding invitation to receive that grace in obedience to the Lord.
While preaching is universal in principle, its primary and natural audience is the covenant community as she gathers together for worship and prayer. This was already modelled by Paul, whose Gentile mission always with sermons in the Jewish synagogue, embracing both the “men of Israel” and the “god-fearers” (Acts 13:16). In 1 Cor 14:24, the apostle likewise assumes that the “outsider” is converted when visiting the prophesying church community. Leaving aside the exceptional missionary activity aimed at unbelieving audiences (as e.g. in Acts 17), preaching normally happens within the church community and addresses that community (including its visitors). To the church is entrusted the Word of God; the church is the pillar of the truth; the church is the temple of the Spirit; and so the church is the place where the gospel sounds first and foremost.
Thus the preaching is naturally directed to the “beloved congregation in the Lord Jesus Christ,” to “brothers and sisters.” A basic attitude of belief in and reverence for God may be presupposed. Covenantal preaching can lay out the doctrines of Christianity without first running through the prolegomena. The Bible is opened as the Word of God, unapologetically. The preacher must address the congregation as those who are under the claim of Christ’s lordship. In short, congregational preaching takes place within the framework of covenant, of an established relationship between the Lord, on whose behalf the preacher speaks, and the audience in the pews who are his people.
In a way, this is the one presupposition necessary for true redemptive-historical preaching: the listeners today stand in essentially the same covenantal relationship as the characters in Scripture’s narratives. This is the presupposition in the reading of the Decalogue, which only applies because the God of Sinai is also Yahweh, their God, who brought them out of the house of slavery.
An emphasis on covenantal preaching is justified and important, but it can be misapplied. It is not difficult to find examples in the history of the Dutch Reformed churches. First of all, covenantal preaching may become presumptive. How easy it is to presume that the church members, who by and large are covenant members, baptized and incorporated in the local church, are therefore also true believers! But if we think this, we fail to sound the gospel warnings, drive home the reality of judgment on unbelief, and instill the fear and trembling with which all of us must implement our salvation. Especially heirs of Schilder should be aware of the parallel of covenant promise and covenant threat; yet in practice it is something we easily overlook.
Improper covenantal preaching may also become exclusive in an improper way. Without saying so explicitly, the preacher can encourage thinking in terms of “us” vs. “them”, where “we” are the church community and “they” are all others. This happens when we start confusing God’s covenant with our denomination, and true believers with those who conform to our customs and expectations. Paul already warned the Colossians and Cretans to keep in mind their pagan past; likewise, the preaching must remind the covenant community that they are by nature just as inclined to evil as those outside.
A third potential pitfall of covenantal preaching is an increase in the difficulty level of preaching. There is certainly room for more advanced topics from time to time, but I am convinced that the main substance of all preaching must be basic gospel preaching, largely understandable even for the outsider and the novice. The unexplained use of Biblical references and theological terms, and any other instances of a tale Kanaäns (Dutch “language of Canaan”, referring to pious, archaic language) must be avoided; it is subject to the same criticism as the public glossolalia in the Corinthians church (1 Cor 14).
While it may seem foolishness to the world, it is God’s wisdom that we all, novices and mature believers, hear the same basic message over and over. There are no advanced grades of covenant membership. Sermons may have a variety of difficulty levels (some things aimed at the understanding of children, some things requiring a bit more advanced thought), but no sermon should be designed specifically for the advanced elite or for the newcomers. I have experienced several attempts by Reformed churches to have “accessible”, laagdrempelige sermons for evangelism purposes; the best of them made me wonder why the minister did not write the same kind of sermons for the covenant community every week!
In the more experiential (bevindelijke) traditions, there is a tendency to separate the audience in a different way: the true believers and the rest. In the most obvious cases, the message is first addressed to “dear friends”, and the last application to the “dear child of God”. The intention is to underscore that the divine promises are only for those who have true faith. Only they can receive the full experience of divine comfort and joy, the full benefits of Christ crucified and risen; others must first be guided to sorrow for sin and self-denial. Such preaching presents the first part of the Heidelberg Catechism to one part of the audience, and the second and third part to the other part of the audience. It separates law from gospel. It is understandable to find this “discriminatory” (onderscheidelijk) preaching in church traditions that deny the free offer of the gospel: the preacher attempts to proffer the benefits of salvation only to the elect. But I have found the same division, though less pronounced, in the Heritage Reformed Churches, which expressly confess the free offer.
In a subtle way, this separation also takes place in the Protestant Reformed tradition, in spite of its aversion to experientialism. In those circles, preaching is “an infallible oath of God’s part that he will bring his elect to glory”, purely objectively. Every audience is invisible divided into two groups: the elect who receive the gospel promise, and the rest, for whom there really is no promise at all.
I reject all such distinctions in preaching; all must hear and obey the same message. All must be called to repentance and faith; all must be driven to Christ for redemption; to all must be laid out the riches of Christ; all must be invited to heavenly joy. The unbeliever must be made to see how beautiful Christ is; the believe may not forget that the divine law condemns him to death.
That is not to say that a preacher should ignore the difference among his audience. On the contrary, he must both comfort the afflicted and afflict the comfortable. It is proper to identify the unbelievers, the hypocrites, the seekers, the faithful, and so on; in fact, all of these people should be addressed personally. “If you sit here, thinking that your baptism will save you even though you do not commit yourself truly to Christ, you are deceiving yourself.” “Even if our faith wavers at times, we can trust the the Lord will complete his work in us.” The traditional Form for the Administration of the Lord’s Supper gives a key example, when it tenderly encourages those who worry about remaining sin, but also speak firmly to those who deliberately persist in sin.
In that sense, gospel preaching must always be experiential, addressing not only facts but the hearts and lives of people. As Trimp points out in his book, preaching is about “Klank en weerklank”: the gospel sound must be made to resound in the hearts of people. Preaching may therefore never be purely objective, merely laying out facts and dogmata. It must place the gospel in the life of the audience, believers and unbelievers alike. It must prod their motivations, it must poke around in their lives, it must convict and comfort, driving home promises and warnings alike. Ideally, no person may leave the sanctuary unexamined, unmoved, unactivated.
What does this mean practically? In the preparation of the sermon, the preacher will consider where his congregation is at. He must not shy away to name sins, worries, and excuses, in general terms but so that people feel convicted. The tone of the sermon should vary naturally from consolation to indictment, from gentle love to rightful indignation. The application lays out moral aspects of the Christian life in realistic detail, and recite praises that stir the hearts. For myself, I have the following principle: don’t speak at a distance of abstract groups of people (“those who doubt”), avoid the trite communal first person (“we may be comforted”), but use the concrete and direct second person: “if you struggle with …, you can take this to heart.” A sermon is no objective lecture, but a personal promise appealing to the entire person.