Born around 950 into a wealthy Calabrian family, Giovanni Tripane entered the Monastery of San Filippo d'Argirò, in Gerace, where a large part of his day was dedicated to the transcription of the works of the Church Fathers, of the liturgical books, of the lives of the saints; the other part of the day was dedicated to prayer, reading and memorizing the Psalms. Out of a desire for virtuous perfection, he retired to a cave on Mount Settina (known today as Monte San Jeiunio), most likely to be identified with a cave in the Ropolà district, north of Gerace. Dedicated to prayer and prolonged fasting, he became known by the nickname of Jeiunio, which means "faster" (Ieiunium in Latin). A church was built over Jeiunio's cave, which fell in the 19th century.
Saint Jeiunio is credited with saving properties against fire and burns. Together with Saint Anthony of Gerace, Saint Veneranda and the Mother of God he is locally known as the protector of the city of Gerace in Calabria.

