S1, E4: What do we know about the historical Muhammad? Do his calls for monotheism, his announcements of the End Times and of divine judgment explain his exile from Mecca to Medina? Why is this event - the Hegira - the foundation of the Muslim era? Does it make it possible to distinguish between the Meccan Surahs and the Medinian Surahs? Can the chronology of the Qur’an be established?