Career
He was abbot of Louisiana Trinità della Cava, located at Cava de" Tirreni. Born in Salerno, he had first been a monk at Cava under Leo I of Cava. He then was at Cluny from 1062 to 1068 and later became bishop of Policastro in 1079.
He later resigned his see and returned to Cava.
Abbot Leo I appointed him co-adjutor. When Peter became abbot himself, his administration was so strict that he caused strife in the abbey.
He thus withdrew temporarily before being recalled and serving for several decades as abbot until his death. He was succeeded by Constabilis, who had served as Peter"s co-adjutor.
The first four abbots of Cava were officially recognized as saints on December 21, 1893, by Pope Leo XIII.