Saint Theoctistus, Bishop of Chernigov, before assuming the episcopal office, pursued an ascetic life at the Kiev Caves monastery. He was one of the great Elders, healing St Nikita, the future Bishop of Novgorod (January 31), by his prayers.
In the year 1103, St Theoctistus was made igumen of the Kiev Caves monastery. In the year 1108 he built a stone trapeza (dining hall) through the generosity of the pious prince Gleb Vseslavich. St Theoctistus particularly insisted that the name of St Theodosius (May 3) be included in the Synodikon of the saints of all Russia.
On February 11, 1110, there was a heavenly apparition at the Caves monastery. A pillar of fire appeared, stretching from the ground to the sky, and lightning lighted up all the earth, At the first hour of the night, there was a crash of thunder. The fiery pillar stood over the stone trapeza so that its cross was not visible. Later, it proceeded to the church and settled over the grave of St Theodosius, and then, turning to the East, it disappeared.
“This was not a pillar of fire, but rather an angelic face,” wrote St Nestor the Chronicler, “because an angel appears thus when there is a pillar of fire, a flaming, as says the Prophet David: Who makes His angels spirits and His servants flames of fire” (Ps. 103 : 4).
In the year 1113, St Theoctistus was consecrated Bishop of Chernigov. The Hieromartyr Monk Kuksha (August 27), enlightening the Vyatichi at this time, belonging to the Chernigov diocese. On May 2, 1115 St Theoctistus participated in the transfer of the relics of holy Princes Boris and Gleb to Vyshgorod, and later in Chernigov near his cathedral he consecrated a church in the name of the holy Princes Boris and Gleb, built in the year 1120 by Prince David of Chernigov. And to the noble Prince Passion-Bearers Boris and Gleb the saint made a sermon on the day of their memory. On August 6, 1123, the Feast of the Transfiguration, St Theoctistus died, and because of the feastday, his memory is kept on August 5.
On one of the lists of the Saints it is said, that he was buried at the Caves monastery. St Theoctistus is also commemorated on September 28, when he is remembered in the 9th ode of the Canon of the Synaxis of the Monastic Fathers of the Near Caves.