These three episodes of gospel proclamation that Luke recounts in Acts 17 -in Thessalonica then Berea then Athens- teach that the gospel spreads in the toughest places. It advances in Thessalonica where religious hostility quickly surfaces. It advances in Berea, where the open-minded people seek to critically examine what Paul teaches before they will be convinced. Luke commends this critical examination, but we have to recognize that the audience was tough-they carefully scrutinized everything they were told. And the gospel began to advance in Athens, among pagan idolaters and philosophical skeptics. The point of the passage is that the gospel advances in the hardest places, among the most critical audiences.