Theodoret of Cyrus (or Cyrrhus) (Greek: Θεοδώρητος Κύρρου) (c. 393 – c. 458/466) was an influential author, theologian, and Christian bishop of Cyrrhus, Syria (423–457). He played a pivotal role in many early Byzantine church controversies that led to various ecumenical acts and schisms. He is considered blessed or a saint by the Eastern Orthodox Church.