Studion

The Monastery of Stoudios, more fully Monastery of Saint John the Forerunner "at Stoudios" (Greek Μονή του Αγίου Ιωάννη του Προδρόμου «εν τοις Στουδίου» Monē tou Hagiou Iōannē tou Prodromou "en tois Stoudiou"), often shortened to Stoudios, Studion, or Stoudion, (Latin: Studium), was historically the most important monastery of Constantinople (modern-day Istanbul), the capital of the Byzantine Empire. The residents of the monastery were referred to as Stoudites (or Studites). Although the monastery has been derelict for half a millennium, the laws and customs of the Stoudion were taken as models by the monks of Mount Athos and of many other monasteries of the Orthodox world; even today they have influence.

The ruins of the monastery are situated not far from the Propontis (Marmara Sea) in the section of Istanbul called Psamathia, today's Koca Mustafa Paşa. It was founded in 462 by the consul Flavius Studius, a Roman patrician who had settled in Constantinople, and was consecrated to Saint John the Baptist. Its first monks came from the monastery of Acoemetae.

The Stoudites gave the first proof of their devotion to the Orthodox Faith during the schism of Acacius (484–519); they also remained loyal during the storms of iconoclastic dispute in the eighth and ninth centuries. They were driven from the monastery and the city by Emperor Constantine V (r. 741–775); after his death however, some of them returned.

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Wikipedia