This sets the stage for what is to come, especially when one considers that it seems to have been well understood by the followers of Jesus that it was the Spirit of God at work to animate Him following His Resurrection, with that Spirit then animating His church (as evidenced by the church working to be kingdom-bringers---bringing heaven to earth---bringing to earth that which looks like the rule of the Creator God through His Messiah).
If this is the case, then when Jesus goes on to say “I will give you the keys of the kingdom of heaven” (Matthew 16:19a), the kingdom of heaven being the hoped-for and expected reality of the covenant God’s rule on earth through His Messiah, which was foundational to Jesus’ message as well as that which His ministry embodied as the hoped-for reality to which it pointed, then Jesus, when speaking of the “keys,” speaks of the church. Talk of keys is then not necessarily an abstraction.
At the same time, believers must always be careful to not confuse the church with the kingdom of heaven. Those who compose the church are the representatives of the kingdom of heaven, but the church is never to be thought of as the kingdom of heaven itself. The church is to be the herald of the Creator God’s kingdom come to earth, and is to be the place of the overlap of heaven and earth. It is to be the locus of binding and loosing. That binding is the binding of the operative powers of death and the many forms that it takes in this world, whereas that loosing is the loosing of people and the creation from those same destructive powers. Can such an assertion be made?
What can be seen in Jesus from the very beginning of His ministry? The Gospels report that He “went throughout all of Galilee… preaching the Gospel of the kingdom, and healing all kinds of diseases and sickness among the people” (4:23). Here Jesus is acknowledged to be performing operations of binding and loosing. It is possible to take a look at all of Jesus’ pronouncements concerning the kingdom of heaven to be found in Matthew and drawing out the analogies of binding and loosing, but rather than do that, it would be more worthwhile to point out that such binding and loosing, though some tend to see it only as acts of healing from physical sickness, were actually social healings as well. This social healing allowed for the recipients of the merciful compassion of the covenant God, through Jesus, to be re-admitted as full participants in the community.
Everywhere that Jesus enacts the kingdom of heaven, thus creating the overlap of the two realms of existence, binding and loosing is occurring. As Jesus is heard saying “Whatever you bind on earth will have been bound in heaven” (16:19b), He needs to be understood to be saying, “Whenever you act on earth in a way that defeat the powers that attempt to continue to mar the Creator God’s good creation, you have introduced the power of the Creator God’s realm of existence (heaven), into the world.”
Bearing in mind that talk of heaven and earth in this context is not locative but demonstrative and practical on the part of believers, then likewise, when Jesus is heard to say things like “and whatever you release on earth will have been released in heaven” (16:19c), rather than hear this with some sense of a vast gulf between heaven and earth, He needs to be heard saying, “Whenever you act on earth in a way in a way that liberates your fellow man, affirming their humanity and bringing them closer to rightly bearing the divine image in which they were created, you enact the power of heaven in the world.”