Saint John, Hermit of Pskov (+1616) lived an ascetic life during a terrible time of military troubles. In 1592 the Swedes besieged the city of Pskov. From 1608, for seven years, Polish forces attacked under the head of Lisovski. It was only in the week before the death of the monk, through the intercession of the Pskov Caves Icon of the Mother of God and the Pskov Saints, that Pskov was delivered from the besieging army of the Swedish king Gustavus Adolphus.

St John, as the chronicle relates, “lived within the city walls for 23 years; his fish was rancid and he did not eat bread. He lived within the city as though in a wilderness, in great silence,” and he died on October 24, 1616.

Source:

https://oca.org/saints/lives/2017/10/24/108923-st-john-the-hermit-of-pskov