The popular worship song "God of This City" was written by Aaron Boyd, lead singer of Bluetree, while they were on a mission trip to Thailand. Near the end of a gig in a bar beneath a brothel in one of the world's sex-trade capitals, Aaron began to sing to the city that "greater things have yet to come / greater things are still to be done in this city." Within a few days, the full lyrics had emerged; within a few months, the song was ringing in Bluetree's hometown of Belfast, where the promise of "greater things" is starting to bear fruit. "God of This City" eventually became the anthem of the Passion international worship conferences, but there is more to the song than an inspiring melody and unusual history. Boyd shares the biblical mandate for God's people to right the wrongs done to the voiceless everywhere. This is a challenge to the Church to live lives of worship marked by actions that will transform a world of cities longing for greater things.