Theodore Syncellus was a prominent member of the clergy in Constantinople in the 620s, being a close advisor to Patriarch Sergius. As such he was chosen to participate in a delicate mission to the Avar khagan during the siege of the city in 626 and to deliver celebratory sermons. The first, 'On the Robe', commemorated the restoration of the miraculous relic of the Virgin's Robe to the shrine at Blachernae, just outside the city walls, after it...