The prayer-book Dala’il al-Khayrat by the Moroccan mystical activist Abu Abdallah Muhammad b. Sulayman al-Jazuli (d. 870/1465) is one of the most successful books in Sunni Islam, after the Qur’an itself. It is known from the Islamic West, where it was written more than five hundred years ago, till far in South-East Asia, and everywhere in between. There must be many thousands of manuscripts of it all over the world, and many hundreds in printed versions. The numerous editions which are currently available in the entire Islamic world prove that the book has lost nothing of its appeal. Most manuscripts and all printed editions of the Dala’il al-Khayrat are provided with two illustrations, showing either elements of the Prophet’s Mosque or views of the Great Mosque of Mekka and the Prophet’s Mosque in Medina. Why these illustrations came to be inserted into al-Jazuli’s prayer-book in the first place, and how they changed from one representation into another is the subject of this lecture.