St. Peter Damian, Italian monk and theologian, Doctor of the Church, c. 1007-1072, author of Liber Gomorrhianus, Officium Beatae Virginis and other works
Fishburn and Hughes: "An Italian ecclesiastic, whose writings are recorded in Migne's Patrology. Damiani was prominent in the eleventh-century reform movement for his attack on simony, his advocacy of celibacy of the clergy and his introduction of severe disciplinary practices, including self- flagellation. From his hermitage near Gubbio, Damiani distinguished himself on a political level by his support of Pope Alexander II in the schism against Honorius IV, and for persuading the Emperor Henry IV of Germany not to divorce his wife Bertha.
In his theological treatise De Divina Omnipotentia (1067), Damiani addresses himself to the question of whether God is able to undo the past. The argument springs from a statement by St Jerome, quoted in the first chapter, that virginity cannot be restored once it is lost through intercourse. Damiani's answer is that God can make a woman a virgin again if she so dedicates herself to the spiritual life as to wipe out the memory other previous actions. Equally God chose to destroy in the flood the men he had once created, for their evil removed them utterly from the sole source of being: though men may survive their bad actions, the negative part of their life is non-existent and can therefore be obliterated. Borges's reference to Canto XXI of Dante's Paradiso is to lines 124-5 in which Damiani refers to a confusion of identity after his death, when he was taken for another 'Pietro', who also founded a monastery near Ravenna and was known as Peccatore, the Sinner, on account of his public life before retiring into the Church." (56)