By St. Nikodemos the Hagiorite
In various times and ways our Lady the Theotokos guarded from many dangers the city of Constantinople which is dedicated to her. During the reign of Leo the Isaurian, who ruled in 716, the Saracens entered Constantinople, and encircled it for three years. However they departed without success. Bede among the Latins writes that when the Bulgarians fought against the Saracens they defeated them, while Kedrenos and Theophanes among the Greeks said that the Saracen fleet was obliterated by the fire-bearing ships of the emperor. Except it was the power of God and the grace of the Theotokos, which guarded the City from the danger.
For if the fortress of Bethulia was guarded by Judith, how much more is Constantinople guarded by the thrice-virgin Maiden Mary, as Gregory says in his letter to Saint Germanos? We sing that the holy icon of the Theotokos was processed on the walls of the City with the utmost reverence. Wherefore she embraces her City. For she says of herself in the Song of Songs (8:10): "I am a wall, and my breasts like towers." Because of this the Akathist Hymn began to be chanted in every church. Death followed the Saracens to the extent that 200,000 of them died. For this reason as well as because of hunger, they were compelled to flee without success.