Theodore was a bishop of Cyrene in Libya during the reign of the emperor Diocletian (284–305). According to the synaxarion he was an accomplished scribe and calligrapher who transcribed many books for the use of the churches, and the influence of his writings in turning people from idolatry to the Christian faith became the immediate occasion of his arrest. He is commemorated on July 4 together with several companions who suffered alongside him.
By tradition Theodore was denounced to the local authorities by his own son, named Leo (also given as Leontius), who reported to the district governor Dignianus that his father possessed Christian books and was leading people away from the worship of the idols toward faith in Christ. Brought before the governor, Theodore was ordered to surrender his books and to renounce Christ, and he refused both demands.
The accounts relate that he was beaten with rods and subjected to prolonged torture, and that his tongue was cut out; he was then cast into prison, where he died of his wounds. Martyred in connection with him were a number of Christians who had received baptism at his hands, among whom the synaxarion names the women Cyprilla, Lucia, and Aroa.