Black St. Benedict Oval Black Rosary. 5 X 7" Oval Bead Size: 20" L, 1 1⁄2" Crucifix. Lay Catholics Are Not Permitted to Perform Exorcisms but They Can Use the Saint Benedict Medal, Holy Water, the Crucifix, and Other Sacramentals to Ward Off Evil. Catholic Saint Benedict Patron Saint of Kidney Disease, Poison Sufferers, Students, Poisoning, School Children, Homeless, Monks.