Book excerpt: The world in which early Christianity developed consisted of a complex of distinct communities and cultural 'layers', which interacted with one another, sometimes co-operatively, and sometimes in confrontation. The Three Worlds of Paul of Tarsus explores this world through the life of the apostle Paul, examining the three fundamental cultural 'layers': * the native cultures * the common Hellenistic culture which had been spread in the east as a result of the conquests of Alexander * the culture of the political overlord, Rome. It shows how Paul, as a Jew, a Greek-speaker and a Roman citizen, participates in all of these 'layers'. The authors give an account of the places Paul visited, showing their historical, cultural and political differences and discuss the varied categories, such as religion, philosophy and language, which constituted identity.