Venerable Nikēphóros of Mount Athos
Saint Nikēphóros was the teacher of Saint Gregory Palamas (November 14). He grew up as a Roman Catholic, but he journeyed to the Byzantine Empire and became Orthodox. Saint Nikēphóros lived as an ascetic on Mount Athos, and died before the year 1300. His treatise “On Watchfulness and the Guarding of the Heart” is found in the fourth volume of the English Philokalia.