Holy Prince Theodore of Smolensk and Yaroslavl and his sons David and Constantine.
St. Theodore was a prince of Smolensk and Yaroslavl in the thirteenth century, in the years of the Mongol yoke, who ruled with justice and built churches in his lands, and received the monastic tonsure before his death in 1299. His sons David and Constantine followed him in piety.
Their relics were found incorrupt in 1463, and they are commemorated together on September 19.
Feast day
On the New Calendar, Theodore of Smolensk and his sons David and Constantine is commemorated on September 19. Churches on the Old (Julian) Calendar keep the feast on October 2 of the civil calendar.
Also commemorated on September 19

Theodore of Tarsus, Archbishop of Canterbury
Hierarch, Θεόδωρος Ταρσού
St. Theodore of Tarsus, Greek monk who became Archbishop of Canterbury.
Zosimas the Hermit of Cilicia
Venerable, Ζωσιμάς ο Ερημίτης
Venerable Zosimas the hermit of Cilicia, who lived at peace with the wild beasts.