Cosmas of Kosino

Venerable Cosmas of Kosino (Cosmas of Staraya Russa) was a Russian monk, companion of Venerable Constantine of Kosino, and died after 1240. He is venerated among the venerable by the Russian Orthodox Church. His commemoration is on 29 July and on the third Sunday after Pentecost, in the Synaxis of the Saints of Novgorod.

No information about his childhood and youth has survived, and the other details of his life are very few and scattered. It is known only that he was a monk in the Novgorod monastery of Venerable Varlaam of Khutyn. At the end of the twelfth century he moved together with Venerable Constantine to a secluded island, three versts from the town of Staraya Russa, and there they founded the Kosino monastery.

When Constantine was dying, in 1240, he wished to leave the abbacy to Cosmas, but the latter refused the rank and continued his labours as a simple monk. It is not known when he died. His relics, together with those of Venerable Constantine, rest under the ground in the Kosino monastery.