Muezzin

[5] The muezzin is not considered a cleric, as he cleans the toilets and the place where people wash their hands, face and feet when they perform the Wuḍu' (Arabic: wuḍū’ وُضُوء, the "purification" of ablution) before offering the prayer.

[7][dubious – discuss] From the fourteenth century, initially in Mamluk Egypt but then spread into other parts of the Islamic world, major mosques might employ a related officer, the muwaqqit, who determined the prayer times using mathematical astronomy.

Unlike the muezzin who were typically chosen for their piety and beautiful voice, the qualification of the muwaqqit required special knowledge in astronomy.

[12] Today, with the production of electronic devices and authoritative timetables, a muezzin in a mosque can broadcast the call to prayer by consulting a table or a clock without requiring the specialised skill of a muwaqqit.

[15][16][17][18] After minarets became customary at mosques, the office of muezzin in cities was sometimes given to a blind man, who could not see down into the inner courtyards of the citizens' houses and thus could not violate privacy.