Confessor under Iconoclasm
The defining episode of Theosterictus's life is the assault on Pelekete during the first iconoclast persecution. The monastery, dedicated to Saint John the Theologian, stood among the Bithynian communities that openly defended the veneration of images, and so drew the hostility of the iconoclast administration of Constantine V. Sources place the attack in the years around 763, when Michael Lachanodrakon, governor of the Thracesian theme and a zealous iconoclast, moved against the monasteries.
Theosterictus survived the slaughter of many of his monks only to face mutilation and imprisonment. That he kept the title of confessor—rather than martyr—reflects that he endured these things and lived, bearing the marks of his disfigurement for the rest of his life. The tradition that he had neither nose, ears, nor fingers when he resumed the abbacy underscores the visible cost of his confession.