The Monk Cornelius Komelsky came from the boyar family of the Kryukovs. His brother Lukian served at the Moscow Grand Ducal court. When Lucian, having reached an advanced age, decided to retire to the monastery of St. Cyril of Belozersky, he was followed by Cornelius, who from an early age aspired to a hermit's life. After taking the veil, young Cornelius began his monastic exploits with hard obedience – in bread, he wore heavy chains, and in rare hours of rest he copied church books. 
Later, for the love of solitude, the Monk Cornelius left the Belozersk monastery and visited Rostov. In Novgorod, Saint Gennady (December 4) tried to keep him with him, but the ascetic settled in a deserted place near Novgorod. When people who aspired to monastic life began to visit him here, he moved to the Tver Savvatiev monastery, and later, in 1497, he settled in the Komelsky forest, near Vologda, where he set up a cell. Monks began to gather at the place of the exploits of St. Cornelius, and in 1501 he built a wooden church on this site in honor of the Entry of the Most Holy Theotokos into the temple. 
In the same year, Metropolitan Simon ordained St. Cornelius to the rank of hieromonk. In 1512, when the number of the brethren increased, the monk built a stone church and wrote a charter for the brethren based on the charters of Saints Joseph of Volotsk and Nil Sorsky. This was the third charter written by a Russian saint for monastics. Venerable Cornelius of Komel was distinguished by his generosity to the poor, and during the famine he provided a shelter for children in the monastery courtyard. For his love for the poor and orphans, the Monk Cornelius was many times honored with the blessed vision of the Monk Anthony the Great (January 17), for whom he had a special reverence and erected a temple in his monastery in honor of the great ascetic. 
The severity of the saint's life aroused the murmur of some of the brethren, and the Monk Cornelius was forced to leave the monastery and settle on Lake Surskoye, 70 versts from his monastery. For some time he also labored in the Trinity-Sergius Lavra. At the request of the monks of the Cornelius Monastery, Grand Duke Vasily Ivanovich urged the monk to return to his monastery. The ascetic obeyed and, returning to his monastery, handed over the abbacy to his disciple Laurentius and shut himself up in his cell.
During the attack of the Tatars on Vologda land, the Monk Cornelius, protecting the brethren, withdrew with them to the Belozersky region. The monk died at the age of 82 on May 19, 1537. Many of St. Cornelius' disciples also became famous for the sanctity of their lives: Saints Gennady of Lyubimograd (January 23), Cyril of Novoezersk (February 4), Herodion of Ilozersk (September 28), Adrian of Poshekhonsky (March 5), Laurentius and Cassian of Komel (May 16).
The church-wide celebration of St. Cornelius (May 19) was established on January 25, 1600 by Patriarch Job and the Council of Bishops. The life of the monk was compiled by his disciple Nathanael in 1589. There is a service and praise for the saint, and the charter, written by St. Cornelius, has been preserved.