Monastic Life on Mount Athos
On Mount Athos, Theonas first lived as an ascetic at the Monastery of Pantokratoros, where he was ordained a priest. He afterward joined the brotherhood of Saint James of Kastoria at the Skete of the Honorable Forerunner above the Monastery of Iveron.
By tradition, on Bright Friday in the year 1518 Saint James and his brotherhood departed from Mount Athos, passing through the region of Thessalonica and settling for about a year at the Monastery of the Honorable Forerunner in Dervekista, in Aitolia. After James was martyred on November 1, 1519, leadership of the brotherhood passed to Theonas, who led the community back to the Monastery of Simonopetra on Mount Athos around 1520.
The Monastery of Saint Anastasia
In 1522 Theonas led his brotherhood from Mount Athos to the outskirts of Thessalonica, where they settled at the Monastery of Saint Anastasia the Pharmacolytria and thoroughly reconstructed it. Under his direction the community grew to about one hundred and fifty monks, and the monastery became a notable center of monastic life in the region.
Theonas served as abbot of the Monastery of Saint Anastasia, by various accounts, until about 1535.
Archbishop of Thessalonica
Theonas was raised to the hierarchical throne of Thessalonica, an elevation that the sources place around 1535; he is attested as Metropolitan by 1538. He governed the see during the hardships of the Ottoman occupation. He is thought to have reposed in peace around 1541.
Relics & Shrines
His relics, reported to be incorrupt, were according to tradition translated in a miraculous manner to the Monastery of Saint Anastasia. In 1821 they were carried to the island of Skopelos and thence to the Monastery of Esphigmenou on Mount Athos, and were afterward returned again to the Monastery of Saint Anastasia, where they are kept and venerated.
