Here is a written excerpt:
The word “church” here is ekklēsia. It’s a word that is often used in the Greek translation of the Old Testament to refer to the “assembly” of all Israel, “the gathered people of God.” The idea, then, is that Jesus is creating a new “assembly” of God’s people, a renewed people of God gathered around him.
That’s probably the idea behind Jesus’ enigmatic statement: “on this rock I will build my church.” He means Peter’s confession—that Jesus is the promised Messiah of Israel—this is the foundation of the church Jesus will build.
In other words, Jesus himself—the Messianic King bringing about God’s kingdom on earth—Jesus himself is the foundation of the restored people of God. As Paul says in 1 Corinthians 3:11, “No one can lay any foundation other than the one that has been laid; that foundation is Jesus Christ.”
The church, then, is all those people who are built upon Jesus, gathered around Jesus, together seeking to walk in Jesus way’ of life, his way of love that brings about God’s reign of justice and peace and joy.
Jesus’ words are a solemn pledge: Jesus will build his church. It’s not we who need to build his church. It’s Jesus’ church, and he will build it. We simply need to be the church, we need to be this new assembly of God’s people gathered around Jesus.
And Jesus’ pledge comes with a promise: Jesus will build his church, and the gates of Hades will not prevail against it.
It’s important we understand what Jesus is saying here. “Hades” is not “hell,” but rather “the realm of death”: the gates of death’s kingdom will not withstand the church Jesus will build. All the consequences of human sin, all the destructive effects of our harmful attitudes and actions—all this “death” with a capital “D”—will be powerless against the people who are gathered around Jesus.
Yes, it’s true: the image Jesus paints here is not a defensive one, as if Death is assaulting us and we are defending our own gates. It’s an offensive attack: we who walk in Jesus’ way of love are storming the very gates of Death.
This means, then, that Jesus’ pledge and promise carry within them the very mission of the church: we are called to walk with Jesus in his way of love, his way of cross-like, co-suffering love, and so take on all the cruelty and hatred, injustice and oppression this world has to offer. Whatever we bind on earth—binding the very powers of evil—has already been bound in heaven. Whatever we loose on earth—liberating the oppressed, bringing freedom to the captives—has already been loosed in heaven.
The church, then, is to be where heaven and earth come together. The renewed people of God, gathered around Jesus, is where we should catch the first glimpses of God’s will being done, God’s kingdom coming, on earth as it is in heaven.