The brothers received an excellent education and were particularly involved in philosophy. Striving towards the knowledge of God, they settled in the [[Lavra]] of St. Sava. Here St. Theophanes was [[tonsure]]d, and later became a [[hieromonk]].
The holy brothers were famed as advocates of [[icon]] veneration. They boldly fulfilled the mission entrusted them by the [[Patriarch of Jerusalem]] and went to Constantinople to denounce the [[iconoclast]] emperor [[Leo V the Armenian|Leo the Armenian]] (813-820). Afterwards, they also denounced the iconoclast emperors Michael Balbos (820-829) and Theophilus (829-842).
The saints had to endure imprisonment, hunger, even torture. The emperor Theophilus gave orders to inscribe a phrase insulting to the glorious [[confessor]]s upon their faces with red-hot needles. Therefore, they are called "Branded." "Write whatever you wish, but at the [[Last Judgment]] you shall read your own writing," said the agonized brothers to the emperor. They sent Theodore to prison, where also he died (+ 833), but Theophanes was sent into exile. With the restoration of icon veneration, St. Theophanes was returned from exile and consecrated Bishop of Nicea. The saint wrote about 150 [[canon (hymn)|canons]], among which is a beautiful canon in defense of holy icons. He died peacefully around the year 850.