The Saint Cyprian venerated today is really a fusion of two individual saints with the same name, Saint Cyprian of Antioch and Saint Cyprian of Carthage. It’s easy to see how the two became entangled over the years, when you consider that they had a great number of similarities including the time period they lived in (300 CE), their positions (archbishops of the Roman Catholic Church), their style of death (martyrs) and possibly their conversion experiences (from pagan sorcerer to servant of Christ).
Though both of the archbishops lived virtuous lives and happily laid them down for their beliefs in Christ, only one of them became restless after his death about a decision he had made in life. As to which one it was, no one will ever know for sure. Because, when the spirit appeared to the German monk, Jonas Sulfurino, several hundreds of years later, he introduced himself only as Saint Cyprian, San Cipriano in Spanish.
In his conversation with the German monk, Saint Cyprian expressed remorse in having burned his vast occult collection of books. It seems he had spent the time since his death considering just how much some of the ancient magic could benefit people. He returned, so he said, to make amends by making the knowledge he had obtained through his books available to all. To do this, however, he needed the help of a fellow monk who would be willing to write down all he dictated and to see to it that the resulting book would be made available to the public. Jonas agreed to help, and the result of their collaborating is The Book of San Cipriano, still a very popular grimoire that has yet to be translated into English (it can be readily obtained in both Spanish and Portugese).
Though quite a controversial book, The Book of San Cipriano continues to have a great influence over Iberian magic. One popular legend about the book claims that the devil can be summoned if it is read backward.
Though the church officially denies that either of the Saint Cyprians returned from the dead to share powerful occult knowledge, many Catholics and pagans alike acknowledge Saint Cyprian as a patron saint of magic who can be petitioned for anything. According to folklore, two of his specialities are exorcism and bringing about love relationships.