Monastic Career
John spent his formative monastic years at Râșca Monastery, where the sources relate that he remained for about eighteen years after his tonsure around 1630. He was afterward moved to Secu Monastery by Metropolitan Varlaam (Barlaam) of Moldavia, to whom the accounts describe him as related.
From 1641 to 1665 he served as hegumen (abbot) of the fortified monastery within the Citadel of Neamț, a foundation associated with Prince Vasile Lupu. In 1666 he was appointed hegumen of Secu Monastery, the house with which—together with Râșca—his name is permanently linked.
Episcopate
In 1667 John was installed Bishop of Huși, a see overseeing the faithful of Lower Moldavia, where he served for about seven years. In 1674 he was translated to the see of Roman, an ancient Moldavian bishopric associated with the Mușatin princely line, and he held this office until his repose in 1685.
Within his native Vrancea region he founded the Mera Monastery, which the sources say he established with modest personal means and, by some accounts, the assistance of his kinsman Vornic Moțoc of Odobești. He is remembered as the spiritual father of Saint Teodora of Sihla, whom he guided in her early monastic life.
Repose, Relics, and Glorification
John reposed in 1685 and was buried at Secu Monastery, beside its principal church, where the sources note that his tombstone remains visible.
The Holy Synod of the Romanian Orthodox Church entered him among the saints in 2008. The Romanian accounts record the formal canonization decision in the spring of 2008, with the solemn proclamation held that year at Neamț Monastery on the Feast of the Ascension, and his name was set for commemoration on August 30 together with Metropolitan Barlaam of Moldavia.