Rev. Key is pastor of the Protestant Reformed Church of Hull, Iowa.

Article 29 of the Belgic Confession begins this way:

We believe that we ought diligently and circumspectly to discern from the Word of God which is the true church, since all sects which are in the world assume to themselves the name of the church. But we speak here not of hypocrites, who are mixed in the church with the good, yet are not of the church, though externally in it; but we say that the body and communion of the true church must be distinguished from all sects who call themselves the church.

The marks by which the true church is known are these: if the pure doctrine of the gospel is preached therein; if she maintains the pure administration of the sacraments as instituted by Christ; if church discipline is exercised in punishing of sin; in short, if all things are managed according to the pure Word of God, all things contrary thereto rejected, and Jesus Christ acknowledged as the only Head of the church. Hereby the true church may certainly be known, from which no man has a right to separate himself.

The marks of the church is a subject that found little development among theologians until the time of the Reformation. There was little need, after all, to talk about the marks of the true church so long as the church was one. But as the church departed farther and farther from the truth of Scripture, and fell under the influence of various heresies, as well as many pagan practices and traditions of men, it was necessary to point out certain characteristics that mark the true manifestation of God’s church in the world. This necessity had particularly to be addressed at the time of the Reformation, and it has continued to be a pressing necessity ever since.

While we confess by faith the existence of “an holy, catholic church,” we are called to unite with that church as it is instituted in the world. And today the church institute is fragmented into literally thousands of different churches. The compelling question, therefore, is this: Where must I belong?

The Belgic Confession gives helpful instruction in answer to that question. Article 29 was written to assist and to instruct the serious-minded so that they might locate this true church. It points us to our duty to find that church, to come to a conviction about it, and in that conviction to join and unite ourselves with it.


Our Chief Means of Evaluation


While we generally speak of three distinct marks that distinguish the true church from the false, there is a primary mark that summarizes the three—purity of doctrine, i.e., the doctrine of the pure Word of God. God’s Word alone is the standard by which we must measure any church that we might join. Ephesians 2 reveals that the church is “built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone.” And Paul writes to Timothy (I Tim. 3:15) that the church of the living God is “the pillar and ground of the truth.”

Purity of doctrine is the chief mark because Christ Himself is the Head of the church. And His presence in the church is a presence as the Word become flesh. He is the One in whom God reveals Himself as the God of truth. Christ is always present in truth, and never in the lie!

But so many churches today claim to have the truth! How are we to evaluate whether or not a church has purity of doctrine?

We would certainly lose our way, unless by prayer and diligent searching we make a careful study of all God’s Word, maintaining the fundamental principle of all faithful Bible interpretation, Scripture interprets Scripture. I emphasize all God’s Word, or what is sometimes referred to as “the whole counsel of God,” because all those who depart from the truth do so by taking only part of God’s Word, at the expense of or in conflict with the rest of God’s Word. And if we will make our judgment of where a given church stands up against that standard of the whole counsel of God, there is no better way to put it to the test than to place its teachings next to our Reformed confessions, where we have the careful summary of the whole counsel of God.

But to make it a little easier to evaluate whether or not a church is bound by the pure Word of God, we may look more carefully at three distinct areas where the truth becomes manifest in a faithful church.


The Pure Preaching of the Gospel


When we speak of these three distinct areas where the truth becomes manifest, or three marks of the true church, we must begin with a careful examination of preaching.

Purity of doctrine comes to first expression in faithful preaching. That is evident in II Timothy 3:16-17, which is given as the basis for the charge to preach the Word, which Paul gives to Timothy in the opening verses of the next chapter.

All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: That the man of God may be perfect, throughly furnished unto all good works. I charge thee therefore before God, and the Lord Jesus Christ, who shall judge the quick and the dead at his appearing and his kingdom; Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all longsuffering and doctrine. For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears; And they shall turn away their ears from the truth, and shall be turned unto fables. But watch thou in all things, endure afflictions, do the work of an evangelist, make full proof of thy ministry.”

Christ’s presence in His church is evident where His Word is faithfully preached. His is a commanding presence. After all, where His Word is faithfully preached, there He speaks, fulfilling His promise in John 10:27, “My sheep hear my voice, and I know them, and they follow me.”

On the contrary, where His Word is not faithfully preached, there must be repentance and a return to the truth, or Christ withdraws Himself. For this reason, as the Belgic Confession tells us later in Article 29, the true church is easily known and distinguished from the false. Where the Word is, there is Christ, and there must you and I be.

When we evaluate the church by the three marks, the mark of faithful preaching is first. On the one hand, it is most easily discernible. But on the other hand, the other two marks—the pure administration of the sacraments and the faithful exercise of Christian discipline—depend upon and safeguard the preaching.


The Proper Administration of the Sacraments


While we will give more careful attention in subsequent articles to the sacraments, it is noteworthy that the Belgic Confession considers a mark of the true church “the pure administration of the sacraments as instituted by Christ.”

The importance of the sacraments is evident from the fact that Christ Himself is present in the administration of baptism and the Lord’s Supper. For that reason we are cautioned against approaching either the sacrament of baptism or the sacrament of the Lord’s Supper out of custom or superstition.

In addition, the abuse of the sacraments involves the church in corporate guilt, and in effect defiles the preaching of the gospel. The sacraments, after all, are seals upon the preaching. Strong is the warning of the apostle in I Corinthians 10:21-22: “Ye cannot drink the cup of the Lord, and the cup of devils: ye cannot be partakers of the Lord’s table, and of the table of devils. Do we provoke the Lord to jealousy? are we stronger than he?” Indeed, Paul gives the better part of two chapters to instructing the church at Corinth as to the importance of the proper administration of the Lord’s Supper.

We might add that most forms of corrupting the sacraments are ways in which the true doctrine of the gospel is corrupted. And those forms of such corruption are many! Let us recognize the importance of “the pure administration of the sacraments as instituted by Christ.”

The Biblical Exercise of Christian Discipline

The third mark of the true church is that of Christian discipline. We can easily forget, but discipline is simply an extension of faithful gospel preaching. Preaching itself is the chief means of discipline, that which constantly calls us to repentance and faith. But it is evident that the welfare of the church depends upon the exercise of Christian discipline.

This mark, as the other two, deserves more extensive treatment in subsequent articles. But no church can stand in the truth without the loving exercise of Christian discipline. For one thing, without Christian discipline, the sacraments are profaned—as was evident in the church at Corinth. But as the apostle also makes clear in I Corinthians 5, without discipline “a little leaven leaveneth the whole lump.” That is, sin permeates the entire body, if not kept in check by the exercise of Christian discipline. And if sin goes unchecked within the congregation, sooner or later the preaching itself will succumb to the stifling pressures of ungodliness, failing any longer to confront sin with the bold call to repentance.

It was not without reason that Paul warned Timothy that “the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears.”

That discipline is a characteristic that must mark a true church is evident from the words of Christ to the seven churches of Asia Minor,Revelation 2 and Revelation 3, where on more than one occasion He warned of the consequence of undisciplined sin, even His own withdrawal.


The Application of the Marks


The marks of the true church are not set before us in the Belgic Confession in order to make a theoretical or categorical judgment of other churches. The approach of the Confession is, “Where am I called to be?”

We recognize that the question is not a matter of one church being true with all others being false. We recognize as well that the “true church” does not mean that there is a church in this world that has reached perfection or purity. The “true church” refers to the manifestation of the holy, catholic church in the midst of the world. Where does she become manifest in a given institution?

You and I stand before the calling to do everything in our power to unite ourselves to the purest manifestation of that true church, the church where the marks most clearly manifest the presence of Christ. That is our calling for God’s sake. That is God-honoring—which must always be our focus. That is also the way of our blessedness.

Nor may we leave such a church for any reason. Our calling is to contribute to the development and strengthening of the true church. To depart is to apostatize. And apostasy is the tool of Antichrist in building his kingdom of darkness. When a church departs from the truth, and as the marks enter into decline, that church sets itself on a course to becoming part of the false church. And especially as the mark of Christian discipline is lost, there is no reversal possible. The call must go forth with urgency, “Come out from among them, and be ye separate!” For one to join or to remain in a false church or a church in the process of becoming a false church is to contribute to the development of Antichrist.

May God give us faithfulness in maintaining and embracing the marks of the true church!