St. Theophan the Confessor was born in Constantinople into a pious and noble family. Theophanes' father was related to the Byzantine Emperor Leo the Isaurian (717-741). Three years after Feofan's birth, his father died, leaving his family in the care of the emperor himself. Feofan grew up at the court and became a dignitary of Emperor Leo the Khazar (775-780). His position required him to marry. In agreement with his bride, Theophan retained his chastity, for in his soul there matured a desire to adopt a monastic image. 
Having once visited monasteries with his wife in the Sigrian region (Asia Minor), Theophan met the visionary elder Gregory Stratigius, who predicted to Theophan's wife that her husband would be awarded the martyr's crown. After some time, Theophanes' wife was tonsured a nun in one of the monasteries of Bithynia, and Theophanes took monastic vows from Elder Gregory. With the blessing of the elder, Theophan established a monastery on the island of Kalonim in the Sea of Marmara and shut himself up in a cell, copying books. Feofan achieved high mastery in this activity. 
Then St. Theophan founded another monastery in the Sigrian region, in a place called the "Great Village", and became its abbot. The monk himself took part in all the monastic works and was an example of diligence and heroic deeds for everyone. He was honored by the Lord with the gift of miracle-working: he healed diseases, cast out demons. In 787, the Seventh Ecumenical Council met in Nicaea, which condemned the heresy of iconoclasm. St. Theophan was also summoned to the Council. He arrived in patched rags, but shone with inspired wisdom in affirming the dogmas of true Orthodoxy.
At the age of 50, the monk became seriously ill and suffered severely until his death. On his deathbed, the monk worked incessantly: he wrote the Chronography, the history of the Christian Church from 285 to 813. This work is still a valuable source on the history of the Church.
After the accession of Emperor Leo the Armenian (813-820), when the saint was already a very old man, iconoclasm resumed. Saint Theophan was forced to accept heresy, but he firmly opposed this and was imprisoned. His monastery, the Great Village, was burned down. After staying in prison for 23 days, the Monk confessor died (+ 818). After the death of the wicked Emperor Leo the Armenian, the monastery of the Great Village was restored, and the holy relics of the confessor were transferred there.