Emperor Leo, whose armies were faring badly against the Arabs, had been persuaded that the making of icons of Christ and his saints was the kind of idolatry for which Israel’s kings had lost battles. John knew better and, out of the reach of Leo’s soldiers,* busily disseminated learned treatises so thoroughly grounded in the Scriptures that they were instrumental in overturning the ban in 787, nearly forty years after John’s death in 749. Towards the end of his life, John composed his masterwork, The Fount of Knowledge, a comprehensive review of Scripture and tradition that was essential reading for centuries afterwards across East and West alike.*
John and his adopted brother Cosmas were, much like their English contemporary St Bede, not only scholars and preachers but also gifted in poetry and music. They composed many collects and hymns (sometimes in friendly competition with each other) and gathered more;* and they established principles of chanting that can still be heard today throughout the Eastern churches. Together, they had an astonishing impact on worldwide Christianity, and we will always have them to thank for those beautiful, mysterious icons, windows on another world.
* John was not completely protected from Leo. According to tradition, the Emperor’s spies tricked Caliph Hisham ibn Abd al-Malik into thinking that John was a traitor and it cost John his hand — though that was not the end of the story. See our post The Third Hand.
* John’s most famous hymn is Αναστάσεως ημέρα (anastáseos iméra), the Canon for Easter Day or Paschal Canon, done into English verse by J. M. Neale (1818-1866) as ‘The day of resurrection! Earth tell it out abroad!’. A prose translation of the whole hymn can be found at OrthoChristian. It includes the hymn The Angel Cried sung in the weeks after Easter. The liturgical book called the Great Ochtoechos (hymns upon the eight tones), which dates back to the ninth century and came from the Monastery of Stoudios in Constantinople, is based on earlier work which the monks at Stoudios credited to St John Damascene and his brother Cosmas.
* The best-known part of this work is called An Exact Exposition of the Orthodox Faith or in Latin, De Fide Orthodoxa. It was much relied on not only in the East but also (thanks to a Latin translation that was not always reliable) in the West, and ‘the Damascene’ was lovingly and reverently cited on many occasions by Thomas Aquinas (1225-1274).