Ques. 83. What are the keys of the kingdom of heaven?

Ans. The preaching of the holy gospel and Christian discipline, or excommunication out of the Christian church; by these two, the kingdom of heaven is opened to believers, and shut against unbelievers.

Ques. 84. How is the kingdom of heaven opened and shut by the preaching of the holy gospel?

Ans. Thus: when according to the command of Christ, it is declared and publicly testified to all believers, that, whenever they receive the promise of the gospel by a true faith, all their sins are really forgiven them of God, for the sake of Christ’s merits; and on the contrary, when it is declared and testified to all unbelievers, and such as do not sincerely repent, that they stand exposed to the wrath of God, and eternal condemnation, so long as they are unconverted; according to which testimony of the gospel, God will judge them, both in this, and in the life to come.

Heidelberg Catechism, Lord’s Day 31

Zion, founded on the mountain,

God, thy Maker, loves thee well;

He has chosen thee, most precious,

He delights in thee to dwell;

God’s own city, who can all thy glory tell?

The Psalmist sang of God’s church, represented in the old dispensation by the mighty citadel of Jerusalem with its massive walls and its strong iron gates. The gate of this spiritual City is pictured as having a lock and key, and a sentinel who is authorized of God to exercise his key power, opening the gate for some and closing it for others. For outside of this Holy City rages the enemy, all the forces of darkness, sin, and hell, wickedly determined to destroy the City and all its inhabitants. Symbolically this represents the key power of the kingdom of heaven, guarding the City of God against the onslaughts of the power of darkness, to the glory of our God, for the welfare of Zion, as a blessing to the citizens of heaven.

Upon Peter’s confession, “Thou art the Christ, the Son of the living God,” Jesus had responded, “And I say unto thee, that thou art Peter, and upon this rock I will build My church, and the gates of hell shall not prevail against it. And I will give thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven, and whatsoever thou shalt loose on earth shall be loosed in heaven” (Matthew 16:18, 19).

Glorious confession! For the Rock upon which Jesus builds His church is not the man Peter, nor Peter as representative of the apostles, but HIM Whom Peter confesses to be the Christ, the Son of the living God. Blessed is that man who experiences the wonder of God’s grace in his own heart and life, whereby He knows and confesses Jesus to be the Christ, the Son of the living God. Flesh and blood cannot reveal that to us. God alone, by the risen and glorified Christ, and through His Spirit in our hearts can so renew us, so enlighten our understanding, that we realize our depravity, sin, and misery, and are driven out to the cross of Calvary, where we make the good confession that Jesus is our Savior, our Lord, and our God! In other words, God makes us citizens of His kingdom, leads us to the gate of the City, where the sentinel, so to speak, recognizes us by our confession, assures us of the forgiveness of our sins, unlocks and opens the gate, saying, “Come, thou blessed, enter thou into the joys of thy Lord!”

This sentinel, you may rest assured, is none other than Christ Himself. He is the foundation upon which God’s church is built, He is the gate, and He is the sentinel, for He is the Way, the Truth, and the Life. In Him, and in Him alone, is all our salvation. To Him is given the authority of God, merited through His death, resurrection, and exaltation at the Father’s right hand, to exercise the key power of the kingdom of heaven. He alone has the power to open and close the gate of the kingdom, to bind and to loose, to declare within or without, to take in and to cast out. This is His own testimony, “I will build My church, and the gates of hell shall not prevail against it.” Our Lord exercises this power through the preaching of the Word from the pulpit, through the divinely ordained ministers, who are properly called by God’s church, and who declare: “So saith the Lord,” expounding the Scriptures in sincerity and truth.

It is our duty to be on our guard against false teachers and preachers who declare the church to be an open city, inviting and urging whomsoever will to enter, assuring them of a false hope of life everlasting. They are interlopers, thieves, and robbers, who plunder the sheepfold of Christ, surreptitiously presenting themselves as ambassadors of Christ, presenting a gospel that appeals to the flesh, corrupting the Scriptures, and deceiving many.

We must insist that the preaching we hear from the pulpit is the sound exposition of the Word of God. We do not attend church on Sunday to hear the philosophies of a man, no matter how brilliant he may seem to be, no matter how fluent in his speech, how beautiful his style, or appealing his voice or person. We come to hear the voice of Jesus calling us out of our lethargy of sin, bringing us to sincere repentance in sorrow of heart, and assuring us upon confession of our sins and forsaking them, that our sins, no matter how great or how many, are forgiven us on the merit of the cross of Jesus Christ, just as really as sinners heard Jesus’ words of peace and comfort while He walked among us here on earth. To hear Jesus speak to us through the preaching we must be sure that the preacher is called in the God-ordained manner. God is a God of law and order. He requires that only Christ shall exercise the keys of the kingdom; and Christ shall do this only as the chief Shepherd of His flock by appointing under-shepherds called by Himself. And Christ refuses to call anyone except through His church, for Christ exercises the key power through the church institute, and through the church institute alone. Thus Christ calls through His church, which is represented by the special offices of ministers, elders, and deacons. The divinely called minister must preach the Word, expound the Scriptures, proclaim the crucified and risen Christ. That is his sole mandate. That alone makes preaching the power of God unto salvation, the Light that penetrates the darkness of the human heart, our sure Guide, the Lamp before our feet and the Light upon our pathway, leading us to the eternal Day.

It must not escape us, that this power of God always works antithetically; that is, it is a savor of life unto life, but also a savor of death unto death. The Jew within the church clamors for signs and wonders, for display of power, for big happenings, while the idol worshiper clamors for the wisdom of the world. To them the preaching of the gospel, centering in the crucified and risen Christ, is always foolishness. Their wicked, rebellious hearts cry out: NO! A thousand times NO. For “This saying is hard, who can believe it?” No one leaves the church quite as he entered. He has been where the Spirit dwells, where Christ is present with His Word, where the saints gather, where the gospel is preached. God’s Word never returns void. It proves the fact that “He who believes in the Son of God has everlasting life, but he who is disobedient to the Son shall not see life, but the wrath of God abides on him” (John 3:36).

Our Catechism suggests four possible uses of the keys of the kingdom. The key of preaching, which is the chief key of Christ, both opens and locks the gate of the kingdom. It opens the gate to draw into the church that which is outside, but actually belongs within. It also opens the gate to drive out those who are within yet belong outside. It closes and locks the gate to keep out those who are outside and belong outside, yet attempt to enter in. And at the same time it keeps in that which is within and must remain in into eternity.

There are those who must be drawn in by the preaching of the Word, even though they are outside. They are known of God as Jesus’ sheep, elect of God from before the foundations of the world, and redeemed by the precious blood of God’s own Son, yet born and reared outside of God’s church and covenant. For their sake the church receives the mandate to go out into all the world and to preach the gospel to all nations, for he who believes and is baptized shall be saved. The great commission is still the calling of God’s church in the world, amazingly evident in Singapore. That does not mean that God never uses the local church and ministry to draw His own unto Himself. Although this must not be considered the chief calling of the local church, as so many do in our day, God does sometimes use the pulpit in the local church to draw His own out of the world into the church. In a sense it can be said that all of us are drawn out of darkness into light and into a richer communion of life with God in Christ, even though we were regenerated and converted in our early infancy.

There are, moreover, those who are within the church institute who must be put out. They are the carnal element that is always present in the sphere of, the covenant. It is not all Israel that is called Israel. Some are born of believing parents and grow up in the church, but are unbelievers, as becomes evident from their sinful walk of life. Others come into the church with ulterior motives, placed there by Satan to destroy the church, like foxes that wreak havoc in the vineyard. The preaching of the Word must be so thoroughly Scriptural that it serves as a power of God exposing them. The Word offends, and also condemns. Often they will leave to seek their refuge in some other church, where the preaching is more to their liking. We must realize that also in them Christ is exercising His power, the power of the Word as a savor of death unto death. They left, for they were not of us.

There are also those who seek admittance into the Christian church even though they are unregenerated citizens of Satan’s kingdom. From sinful motives they attend the services for a while and then apply to the consistory to be accepted as members of the congregation. Maybe they married someone who is already a member of the church. Maybe they consider it to be to their advantage to become a member of that particular congregation. Whatever the motive may be, Satan is trying to bring his forces as a fifth column into the church, wolves in sheep’s clothing. As eager as the congregation may be to receive new members, the office bearers must be on their guard against such evil workers. If such individuals still somehow find their way into the congregation, the preaching must be so positive that this carnal element cannot hold out without exposing itself, and ultimately being placed outside the kingdom.

Finally, there are those within the church who also have a rightful place there, as is evident from their hearty confession that Jesus is the Christ, the Son of the living God. Since they are still imperfect saints, they must always be warned against a sinful walk of life. The preaching must keep them within the fold, causing them to grow in the grace and knowledge of Christ, into an ever closer communion with the living God. They are kept by the power of God through faith, even unto the end, by the powerful Word of Christ brought to them through His ambassadors.

The faithful servant of Jesus Christ is unto God a sweet savor of Christ, in them that are saved, and in them that perish (II Cor. 2:15). To God be the glory now and evermore!