5 minutes by Acts scholar Craig Keener. Acts 17:18. With background information (minus excursus on the philosophic schools, in adjacent video material from which this was excerpted). For 23 free lectures on Acts, see http://faculty.gordon.edu/hu/bi/ted_hildebrandt/DigitalCourses/00_DigitalBiblicalStudiesCourses.html#Acts_Keener