Finding Common Ground

Acts 17:16-34 Our world in Houston, Texas is a different place than it was a few years ago in more ways than one.  There once was some degree of "common ground" about the nature of truth and presuppositions most people had about God, the Bible, Jesus, man, etc...  Today "common ground" is frustratingly harder to find in our conversations.  How do we engage the task (mission) of sharing Jesus with a Post-Christian world?