LORD’S DAY 31
- What is the Office of the Keys?
The preaching of the Holy Gospel and Christian discipline; by these two the kingdom of heaven is opened to believers and shut against unbelievers.1
 Matt. 16:18–19; 18:18; *Jn. 20:23; *Lk. 24:46–47; *1 Cor. 1:23–24.
- How is the kingdom of heaven opened and shut by the preaching of the Holy Gospel?
In this way: that, according to the command of Christ, it is proclaimed and openly witnessed to believers, one and all, that as often as they accept with true faith the promise of the Gospel, all their sins are really forgiven them of God for the sake of Christ’s merits; and on the contrary, to all unbelievers and hypocrites, that the wrath of God and eternal condemnation abide on them so long as they are not converted.1 According to this testimony of the Gospel, God will judge men both in this life and in that which is to come.
 Jn. 20:21–23; *Acts 10:43; *Isa. 58:1; *2 Cor. 2:15–16; *Jn. 8:24.
- How is the kingdom of heaven shut and opened by Christian discipline?
In this way: that, according to the command of Christ, if any under the Christian name show themselves unsound either in doctrine or in life, and after several brotherly admonitions do not turn from their errors or evil ways, they are complained of to the Church or to its proper officers; and, if they neglect to hear them also, are by them denied the holy sacraments and thereby excluded from the Christian communion, and by God Himself from the kingdom of Christ; and if they promise and show real amendment, they are again received as members of Christ and His Church.1
 Matt. 18:15–18; 1 Cor. 5:3–5, 11; 2 Thess. 3:14–15; 2 Jn. 1:10–11.
Lord’s Day 31
The Church’s Duty to Use the Keys of the Kingdom
This Lord’s Day reading answers a question that would have naturally arisen at the end of the last Lord’s Day, where the Catechism tells us that those who are unbelieving and ungodly must be excluded from the Lord’s Supper by the Office of the Keys. So what is the Office of the Keys?
The expression refers to Jesus’ statement that He would give the keys of the kingdom to the Apostles in Matthew 16:18-19. The Roman Catholic Church believes the keys were given to Peter specifically as the first pope, but similar passages like Matthew 18:18 and John 20:23 are addressed to the apostles as a whole, not just to Peter. The apostles were instructed to found the church. The keys belong to the church as a whole. In many passages the Scriptures command the church as a whole to exercise these functions (1 Cor. 5; 1 Tim. 2:4; Titus 2:15).
Christ gave to the church the function of declaring on what basis people can be part of the kingdom of God. The church does not make someone elect or not elect and cannot discern someone’s heart. But the church, nonetheless, has an important function to perform. First, in its preaching, the church declares the Gospel of Jesus Christ. Faith in the Gospel is the basis by which people can be part of the kingdom of God. God gives this duty to the church, to proclaim this Gospel message, and by doing so declares the criteria by which people can consider themselves in the kingdom of God or not.
The church is not given this declaration as just words. It is to back up the words with action, accepting or excluding people as members on the basis of whether they profess faith in these things and show a life that reflects that faith. This is Christian discipline. Discipline starts with the training of the church in how we as Christians are to repent of our sins and strive to conform our lives to God’s law in thankfulness for our salvation. It continues in personal exhortations, by members or by church leaders, calling one another to put away sin and live godly lives. If necessary, it can go as far as official action by the church to exclude individuals from the Lord’s Supper and ultimately from membership when, over a period of time and much patient work by the church, they refuse to hear the church’s corrections and persist in unrepentant sin. The church never excommunicates people for being sinners, since then there would be nobody in the church. The church excommunicates people for being rebellious and stubborn in their sin, for refusing to even acknowledge that they need to change. This should never be done hastily, yet there are always cases when it must be done if we are to be faithful to our Lord’s commands.
When it is done right, then the church in its membership and discipline practices will be a visible declaration to the world of how it is that people enter the kingdom of God, by repentance and faith. That’s why it is so important that the church do this- not because we will ever be able to discern the true state of men’s souls or because we can make someone saved or not saved solely by an act of the church, but because when the church is being faithful to this calling, it visibly declares to the world the way of salvation. If we do not do so, and preach peace with God to the world on some other basis than repentance and faith in Christ, then the blood of condemned sinners will be on our hands. If we knowingly admit people to membership in the church who do not believe the gospel or who have no commitment to repentance, then we have obscured the way of salvation and will earn the wrath of God as a result.
Being faithful to these Scriptural requirements is guaranteed to make us enemies. We are naturally rebellious and do not like to hear bad things about ourselves. People will resent being told that they have to conform themselves to a particular standard of belief and behavior in order to be members of the church. In our pride, we want to believe that we can dictate the terms of our relationship with God. There is a reason why the false prophets of the Old Testament got rich saying “peace, peace” to the people, while men like Jeremiah who called them to repentance got thrown in a pit. But the Scriptures so clearly require this on page after page that it is impossible to miss it. Churches that desire the approval of the world will flatter people’s claim to have the right to believe what they want and will make people comfortable in their sin. But churches that desire the approval of their Master and Founder will do what He told us, to preach repentance from sin and faith in Christ to the world, and to clearly hold that out as the only way to salvation. The use of the Keys of the Kingdom, of the preaching of the Gospel of Christ and the exercise of Christian discipline, is a high and dangerous calling that the Lord has given His church, and He will reward those who are faithful to that calling regardless of the seductions and threatenings of the world.