Foundation of the Tsilibinsk Monastery
Demetrius founded the Archangel Tsilibinsk wilderness monastery, situated in territory that later fell within the Vologda diocese. As part of this foundation he built a church dedicated to the Archangel Michael, intended to serve the newly converted population of the region.
Beneath the church he dug out a cave, where, according to the synaxarion, he lived for a long time in solitude. This pattern of pairing a community church with a hermit's cell reflects the wilderness monasticism characteristic of the northern Russian forests in this era.
Disciple of Saint Stephen of Perm
Demetrius was a devoted follower of Saint Stephen of Perm (commemorated April 26), the missionary who evangelized the Zyrian, or Komi, people along the Vychegda and Vym rivers. Stephen, born around 1340 in Ustyug, took monastic vows in Rostov, learned Greek, and around 1376 began his mission, devising the Old Permic script rather than imposing Church Slavonic on his converts.
The bishopric of Perm was established in 1383, with Stephen consecrated as its first bishop; he died in Moscow on April 26, 1396, and was canonized in 1549. Demetrius's work building a church for 'the newly converted' situates him within this missionary effort to bring the peoples of the far north into the Church.
The available accounts of Stephen of Perm do not themselves name Demetrius or the Tsilibinsk monastery; the connection rests on the synaxarion's notice of Demetrius as Stephen's disciple.