A monk at the service of the Church

Peter Damian is one of the most well-known writers of the 11th century and one of the greatest advocates of the pre-Gregorian reform, along with several Popes who fought against the evils afflicting the Church at that time – in particular against simony, the buying and selling of an ecclesiastical office or dignity and Nicolaism, which rejected celibacy. With his advice and without taking radical positions, he served the Popes and wrote about these themes in Liber Gratissimus.