Venerable Hierarch Theonas, Metropolitan of Thessalonica

Hierarch Theonas labored on Mount Athos at the turn of the 15th-16th centuries, first at the Pantokrator monastery, then at the Sheria skete of St. John the Forerunner, where he became a devoted disciple of the Venerable Martyr Jacob of Kostur (tonsured at Dochiariou Monastery, who restored the abandoned Iviron skete of the Forerunner near Kostur/Dervekista). When the Ottoman authorities arrested Jacob on a false charge of inciting rebellion, Theonas voluntarily followed him into prison to give him spiritual support. Jacob and two of his companions (the hierodeacon James and the monk Dionysius) were martyred around 1519/1520. Theonas then took over leadership of the brotherhood, which relocated first to Simonopetra on Athos and then to the Monastery of St. Anastasia the Pharmakolytria near Galatista, close to Thessalonica, growing it to about 150 monks. Theonas's pastoral gifts led to his election as Metropolitan of Thessalonica after 1535. He died in 1541; his incorrupt, fragrant relics rest at St. Anastasia Monastery alongside those of the Venerable Martyr Jacob and his companions.

NOTE: the original entry named Theonas's teacher "Jacob the Iberian" — this appears to be an error (or confusion with an entirely different, much earlier, 10th-century saint connected to the founding of the Georgian Iviron Monastery on Athos); the most detailed and internally consistent sources name the teacher as Jacob of Kostur (of Dochiariou). A miracle-working icon of the Theotokos sometimes associated with Theonas's name in some sources could also not be confirmed and has been excluded from the text as unverified.