Saint Hilarion of Gdov and Pskov Lake, was a disciple of Saint Euphrosynus of Pskov (May 15). In 1460 on the banks of the River Zhelcha, not far from Gdov, he founded the Ozersk [Lake] Monastery of the Protection of the Mother of God. The monastery bordered the territory of the Livonian Knights, and the monks constantly suffered the incursions of that military order. Despite harsh conditions and insufficient means, Saint Hilarion maintained a high level of pious and ascetic life at the monastery, and made great efforts to adorn and build up the monastery.
Saint Hilarion reposed on March 28, 1476 and was buried in the church of the Protection of the Most Holy Theotokos in the monastery he founded. Afterwards, a church was built at the monastery in honor of the Nativity of Christ. The left chapel was dedicated to the founder of the Gdov monastery. Saint Hilarion of Gdov is also commemorated on October 21, on the Feast of his heavenly patron and namesake.