Although Peter once accused himself of idleness in his youth, he could not have been idle too long, for at the age of 19 he received a master’s degree from the university at Cologne. Soon afterwards he met Peter Faber, the first disciple of Ignatius Loyola, who influenced Peter so much that he joined the recently formed Society of Jesus.
After his ordination in 1546, he became widely known for his editions of the writings of Saint Cyril of Alexandria and St. Leo the Great. Besides this reflective literary bent, Peter had a zeal for the apostolate. He could often be found visiting the sick or prisoners, even when his assigned duties in other areas were more than enough to keep most people fully occupied.
In 1547 Peter attended several sessions of the Council of Trent, whose decrees he was later assigned to implement. After a brief teaching assignment at the Jesuit college at Messina, Peter was entrusted with the mission to Germany—from that point on his life’s work. He taught in several universities and was instrumental in establishing many colleges and seminaries. He wrote a catechism that explained the Catholic faith in a way which common people could understand—a great need of that age.
At 70, Peter suffered a paralytic seizure, but he continued to preach and write with the aid of a secretary until his death in his hometown (Nijmegen, Netherlands) on December 21, 1597.