“There a few important ramifications that flow from understanding the kingdom of God as his redemptive rule. For one thing, understanding that the kingdom is a dynamic, relational word rather than a geographic one keeps us from thinking that ‘extending the kingdom of God’ is the right way to describe planting trees or delivering hot meals to the homeless.
“Sometimes people talk as if by renovating a city park or turning a housing slum into affordable, livable apartments, we are extending God’s reign over that park or that neighborhood. We’re bringing ‘order from chaos,’ someone might say, and therefore expanding the kingdom.
But as we’ve seen, the kingdom isn’t geographical. Rather it is defined relationally and dynamically; it exists where knees and hearts bow to the King and submit to him. And therefore you cannot ‘expand the kingdom’ by bringing peace and order and justice to a certain area of the world.
Good deeds are good, but they don’t broaden the borders of the kingdom. The only way the kingdom of God – the redemptive rule of God – is extended is when he brings another sinner to renounce sin and self-righteousness and bow his knee to King Jesus.”
What Is The Mission Of The Church? (Kevin DeYoung, Greg Gilbert; p. 121)