In 1712, his father enrolled the seven-year-old Joachim in the Kiev Spiritual Academy. Within the walls of the academy he felt attracted to monastic life. For seven years he studied it further, and finally revealed his intention to his parents.
For a long time his mother and father pleaded with their first-born son not to accept monastic tonsure. But in 1725, unknown to them, he became a “rasophore” (“robe-wearing novice”) with the name Hilarion at the Kiev Mezhigorsk monastery, and on 21 November 1727 he was tonsured in the mantya with the name Joasaph at the Kievo-Bratsk monastery. This event coincided with the completion of his studies at the spiritual academy.
After the death of His Grace Barlaam, the See of Kiev was governed by Archbishop Raphael Zaborovsky. Archbishop Raphael noticed the abilities of the young ascetic and assigned him to greater service to the Church. He was entrusted with the responsibility of the office of examiner of the Kiev archbishopric.
In November 1734, Archbishop Raphael ordained the hierodeacon Joasaph as hieromonk, and he was transferred from the Bratsk monastery school to the Kiev-Sophia archbishop’s house. At the same time, he was appointed a member of the Kiev religious consistory.
In fulfilling the office of examiner, he exerted much effort towards the correction of moral deficiencies among the parish clergy. The saint’s service in the consistory office enabled him to develop his administrative abilities. During this time, he made a good study of the needs of clergy-servers, noting both the good points and the failings of the diocese. His talent for administration was combined with his great spiritual effort. He quickly ascended the ladder of spiritual perfection, which can be seen in his work, “The Conflict of the Seven Venerable Virtues with the Seven Deadly Sins.”
On June 24, 1737 Hieromonk Joasaph was appointed head of the Holy Transfiguration Mgarsk monastery, and elevated to the rank of igumen. Here he worked with all his strength to put the monastery in good order, for it was an old bastion of Orthodoxy in the struggle with the Unia. In this monastery were relics of Saint Athanasius, Patriarch of Constantinople and Wonderworker of Lubny (May 2). Several times Saint Athanasius appeared to Igumen Joasaph, as a sign of his patronal protection.
In 1744 Metropolitan Raphael elevated Igumen Joasaph to the dignity of archimandrite. Towards the end of that same year he was called to Moscow and soon, at the direction of the Most Holy Synod, he was appointed vicar of the Holy Trinity Sergiev Lavra monastery. At this monastery of Saint Sergius he also unstintingly fulfilled obedience to the Church (this year required much exertion for the rebuilding of the monastery after a fire).
On June 2, 1748 at the Peter and Paul cathedral in Peterburg, Archimandrite Joasaph was ordained Bishop of Belgorod. Ascending the archbishop’s throne, Saint Joasaph strictly concerned himself with piety and the condition of the churches, with the proper celebration of divine services, and especially with the moral condition of his flock.
The saint devoted great attention to the education of the clergy, and the correct observance of churchly norms and traditions. Just as before, the saint worked with all his strength in his archpastoral service, without regard for his health.
On the eve of his repose, the saint forbade his cell attendant Stephen to aspire to the priesthood, and he predicted that if he did not obey him, he would meet with an untimely end. To another cell attendant Basil, the saint indicated that he would be a deacon, but would never become a priest. Later, this prediction was fulfilled. Saint Joasaph died on December 10, 1754, and was glorified on September 4, 1911.