Isaija the Monk (Serbian: Инок Исаија or in English: Inok Isaija; ca. 1300–after 1375), also known as Elder Isaija (Elder Isaiah) (Старац Исаија) and Isaija of Serres (Elder Isaiah of Serres) (Исаија Серски), was a 14th-century Serbian monk, one of many Serbian monk-scribes in the Middle Ages who translated ancient Greek manuscripts into the Serbian recension of Old Church Slavonic. His major work is the translation of the works of Pseudo-Dionysius the Areopagite from Byzantine Greek. Isaija's commentaries on political events occur in the context of the fall of the Serbian principality of Serres in 1371, which led the descendants of these local governors to accept Ottoman suzerainty.[1]
As a young boy, Isaija joined the monastic life of the Serbian Orthodox Church affiliated to St. Joachim of Osogovo Monastery on Osogovo Mountain in northern Macedonia, and then to Hilandar Monastery on Mount Athos in Greece, where he spent the rest of his life. In Hilandar, he worked as a translator and became very respected by Serbian rulers as attested to by the anonymous author of The Life of the Monk Isaija, probably written in the late 14th century.
Isaija was a very prominent individual during the reign of Stephen Dushan and Lazar of Serbia. He was a monk with an excellent reputation and he also excelled as a writer, translator, and diplomat. Between 1353 and 1363 he travelled throughout Serbia; he later served as a Serbian diplomat, and he proved to be very skilled during the negotiations initiated by Prince Lazar in order to reconcile the Serbian and the Greek Church, which was achieved in 1375 after resolving difficult diplomatic and ecclesiastical issues with Patriarch Philotheus I of Constantinople. Isaija's dragoman on the mission to Constantinople was Nicodemus of Tismana, Prince Lazar's relative.
At the end of his Pseudo-Dionysius the Areopagite translation, Isaija added an inscription and used a cryptogram to write his name.
Isaija had an anonymous disciple, known only as Isaija's Disciple, who wrote the biography of "Isaija the Monk". No biographical data of this author is extant. He is known in Serbian literature only as Nepoznati Svetogorac, the Anonymous Athonite.