The Inferno Canto XXVIII
Dante is disgusted by the torments of the ninth chasm, where the men who sow scandal and schism are punished. He sees one ripped from chin to crotch with his entrails hanging between. This is Mahomet, who in founding Islam, altered the Christian faith and divided it. His nephew, Ali, is cleft from chin to forehead nearby. Their wounds are continually reopened by a guardian demon. Virgil informs him that Dante is still alive and will return to the living world, whereupon Mahomet tells him to warn Fra Dolcino, a politically divisive contemporary of Dante's, to stop the works he has set in progress if he wants to escape this chasm. Other souls present themselves to Dante, disfigured to match their crimes. Pier da Medicina, split through the throat, missing a nose and an ear, was principally guilty of setting the families of Polenta and Malatesta against each other. Curio, with split tongue, advised Cæsar to go forward with divisive maneuvers that he at first doubted. Mosca de' Lamberti of Florence, with both hands cut off and spurting blood, was guilty of advising the murder of Buondelmonte, which was the event that triggered the feud between the Guelfs and Ghibellines. Bertrand de Born carried his severed head before him like a lamp. "Of itself it made for itself a lamp, and they were two in one, and one in two; how this can be, He knows who so ordains." Canto XXVIII, pg. 151 He is thus punished because he created strife between father, Henry II, and son. Betrand compares his role to that of Ahithophel who counseled Absalom to conspire against his father, the Jewish king David.