[citation needed] Around 1058, Ottone, then a knight, took part in a military action in defence of the Pope against rebel lords in the area of Frascati.
Thus miraculously set free, he went on pilgrimage to the Abbey of Cava de' Tirreni, where under the direction of the abbot Pietro he followed the Rule of St Benedict, dedicating himself to prayer and manual labour.
In 1120 he decided to enter upon the life of a hermit and withdrew into seclusion close to the church of Saint Peter, now known as San Pietro dei Reclusiis, and built a small cell where he prayed, kept vigil, did penance and fasted.
(In the Synodicon Diocesanum Sanctae Beneventanae Ecclesiae of 1686 it is reported that the relics of Saint Ottone Frangipane were preserved in the parish church of San Pietro at Montemiletto).
The most important miracle recorded of Ottone took place in around 1180, when the Saracens of Lucera who were besieging Ariano were struck down by a rain of pebbles by the intercession of the saint, who appeared among the clouds.