Constantine, Michael, and Theodore were a princely family of the city of Murom in Rus', commemorated together on May 21 as wonderworkers of that city. By tradition Constantine, a descendant of Saint Vladimir the Enlightener of Rus', asked his father, Prince Svyatoslav of Chernigov, to grant him Murom, which was at that time still inhabited by pagans, so that he might bring the Christian faith to the land. The sources place the three saints in the eleventh and twelfth centuries.
The tradition relates that Constantine first sent his son Michael ahead of him to the people of Murom as an emissary, but the pagans killed him. When a hostile crowd later threatened Constantine's own life, the prince came out to them carrying an icon of the Mother of God afterward known as the Murom Icon; the synaxarion relates that the people unexpectedly grew quiet and consented to receive baptism, which took place at the River Oka.
Constantine built a church in honor of the Annunciation at the place where Michael had been killed, and later a second church dedicated to the holy passion-bearers Boris and Gleb. With his surviving son Theodore he labored to spread the Christian faith among the people of Murom. Constantine died in 1129 and was buried in the church of the Annunciation beside his sons Michael and Theodore. By the Russian tradition the three were formally numbered among the saints at the Moscow council of 1547.
