In Matthew 16:19 Jesus taught his disciples about the keys of the kingdom:
I will give you the keys of the kingdom of heaven; whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven (NIV).
Because the teaching of the keys of the kingdom is a biblical teaching, it shows up in Reformed Creeds and Confessions (e.g. WCF XXIII.iii, XXX.ii; HC Q/A 83). The keys are the preaching of the gospel and church discipline. Speaking of the keys, Zachariah Ursinus, the primary author of the Heidelberg Catechism, gave a helpful explanation of the keys:
The keys of the kingdom of heaven consist of two parts: the preaching of the Gospel, or the ministry of the Word, and Christian discipline, to which excommunication belongs; by these two the church opens and shuts, binds and looses. It shuts and binds, by the preaching of the Gospel, when it declares and testifies to unbelievers and hypocrites, that they stand exposed to the wrath of God and eternal condemnation, so long as they are unconverted; and it opens and looses when it declares and testifies to the faithful and penitent the remission of sins and the grace of God, for the sake of Christ’s merits. It shuts and binds by Christian discipline, when it excommunicates wicked and obstinate offenders, or forbids them the use of the sacraments, by which they are excluded from the Christian church, and by God himself from the kingdom of Christ; and it opens and looses, when it again receives the same persons, if they repent, as members of Christ and his church.
This distinction, however, must be observed, as it respects the order of those two parts: The keys, by the preaching of the Gospel, first loose and then bind; but, in Christian discipline, they first bind and then loose. Again; the keys loose and bind the same or different persons, by the preaching of the Gospel; but they bind and loose the same persons only, by Christian discipline. Excommunication is the rejection, or the excluding of a gross offender—one that is openly wicked and obstinate, from the society of the faithful, by the judgment of the elders, with the consent of the whole church, done in the name and by the authority of Christ, and of the Holy Ghost, in order that the offender, being thus put to shame, may repent, and that such things as bring a reproach upon the cause of Christ, may be carefully guarded against. This is not merely an exclusion from the sacraments, but from the whole communion of the faithful, with which the obstinate and disobedient have no connection. It is two-fold: internal, which belongs to God alone; and external, which belongs to the church. The former is declared on earth by that which is external; whilst the latter is ratified in heaven by that which is internal, according to the promise of Christ; “Whatsoever ye shall bind in earth, shall be bound in heaven.” (Matt. 18:18.)
Shane Lems
Covenant Presbyterian Church (OPC)
Hammond, WI, 54015
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