Rev. Kuiper is pastor of Southeast Protestant Reformed Church in Grand Rapids, Michigan.
Of the eight occurrences of the word key or keys in the Scriptures, only one has a purely literal meaning (Judges 3:25). The other Old Testament occurrence has both a literal and a symbolic idea, of which more later. All the New Testament uses are symbolic and speak of authority to open and close the kingdom of heaven. The words in the original have simple meanings: to open wide, an opener, a key; to close, shut up, a key.
In Isaiah 22 we read of Eliakim, who was appointed by God to be prefect of the palace of King Hezekiah. He is given the “key of the house of David,” i.e.; he would decide who would enter the king’s palace and have audience with the king. By exercising this authority, this servant of God was a type of Christ who “hath the key of David, who openeth and no man shutteth; and shutteth, and no man openeth” (Rev. 3:7). Jesus has authority to open and close the door to the heavenly palace and presence of God. Jesus pronounced woe upon the lawyers of His day (those skilled in the law of Moses), for they took away “the key of knowledge,” entering not in themselves, and hindering others from entering in. Here the key of knowledge is entrance into the kingdom of heaven through Christ, as Christ was set forth in the Old Testament Scriptures. Rather than opening the way of salvation by the right interpretation of the law, they took away the key, so that really there was no opening, no entrance. Their legalism was an illegal use of the keys!
In distinction from the sword power of the state, the financial power of the employer, and the corporal power of parents, the church has been given by Jesus Christ key power relative to the kingdom; He who has this great authority Himself (Rev. 1:18; Rev. 3:7; Rev. 9:1; Rev. 20:1) entrusts such authority for its exercise to officebearers whom He calls and qualifies. We read of this in Matthew 16:19, where Jesus speaks not only to Peter but to all the apostles, and not to the apostle alone, but to all elders until the end of time: “And I will give unto thee the keys of the kingdom: and whatsoever thou shalt bind on earth shall be bound in heaven; and whatsoever thou shalt loose on earth shall be loosed in heaven.” The keys of the kingdom are the preaching of the gospel in faithfulness to the Scriptures and the administration of Christian discipline in the punishment of sin (see Belgic Confession, Art. 29). To understand how the kingdom of heaven can be opened and shut by the use of these keys, see the Heidelberg Catechism, L.D. 31. In Answer 84 we are given a definition of faithful, antithetical preaching that the church must hear, and insist on hearing, today. The basis for this description of preaching that can serve as key power is such a passage as Isaiah 3:10, 11: “Say ye to the righteous, that it shall be well with him: for they shall eat the fruit of their doings. Woe unto the wicked! It shall be ill with him: for the reward of his hands shall be given him.”
In summary, key power implies: 1) That the sovereign God of heaven and earth has bestowed all power and authority upon Christ as part of His Mediator’s glory when He ascended into heaven. 2) Christ exercises this authority from heaven through pastors (the faithful preaching of the full counsel of God) and elders (the patient, careful disciplining of church members). 3) That the church of Christ must concern herself with the sins of her members which are public and unconfessed. Elders are required to form judgments regarding the doctrine and life of persons under their spiritual care. These judgments, properly made, are identical to the retaining or forgiving of sins. And, when elders do this work in harmony with the Scriptures, what is done by the church through her elders is valid before God in heaven! No little thing to be an elder! No little thing to come under Christian discipline!
And no little blessing to belong to a congregation and denomination where the keys are not rusty but used! Key power protects the preaching of the gospel from heresy and the administration of the sacraments from superstition. It protects the believer from the motions of sin in his members. It protects the entire congregation from profaning the covenant and bringing down the wrath of God upon her. A church that exercises the keys is a safe habitation for believers and their children.