The Prophet Muhammad preaching his final sermon to his earliest converts, on Mount Ararat near Mecca; taken from a medieval-era manuscript of the astronomical treatise 'The Remaining Signs of Past Centuries' by the Persian scholar al-Biruni; currently housed in the collection of Edinburgh University Library, Scotland. Representations of the Prophet Muhammad are controversial, and generally forbidden in Sunni Islam (especially Hanafiyya, Wahabi, Salafiyya). Shia Islam and some other branches of Sunni Islam (Hanbali, Maliki, Shafi'i) are generally more tolerant of such representational images, but even so the Prophet's features are generally veiled or concealed by flames as a mark of deep respect.