Matthew 16:19
I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven. The keys of the kingdom — the authority to open and close access to the kingdom — are given to Peter and (through him, as Matthew 18:18 makes clear) to the church. The binding and loosing authority given to Peter is the authority to declare what is permitted and what is forbidden, what is included and what is excluded, in the kingdom's community. The heavenly ratification of earthly decisions communicates the divine authority behind the church's community governance.