Murder of Severinus

The murder of Severinus of Sankt Wendel marks the climax of the abbey's escalating violence, transforming a series of mysterious deaths into a direct, brutal confrontation over a forbidden book. As the herbalist who had unwittingly become the custodian of Aristotle's lost second book of the Poetics, Severinus is killed by Malachi of Hildesheim, the librarian acting on the orders of Jorge of Burgos, who seeks to suppress the dangerous text at any cost. The crime is discovered almost immediately, and the innocent Remigio of Varagine is arrested for it, sealing the fate of the abbey's investigation and setting the stage for the final confrontation in the finis Africae.

Discovery and the Forbidden Book

Earlier on the fifth day, Severinus had urgently summoned William of Baskerville to the infirmary, whispering that he had found a strange book—a composite volume containing Arabic, Syriac, and Greek texts—that was not his own. This was the very book Berengar of Arundel had stolen from the finis Africae after Venantius of Salvemec's death, and which Berengar had left in the infirmary before his own fatal bath. Severinus, recognizing its importance, had put on leather gloves to handle it, a precaution that later proved crucial: the pages of the Greek section were coated with a slow-acting poison that blackened the fingers and tongue of anyone who touched them. Before he could show the book to William, their conversation was interrupted by Jorge of Burgos, whose acute hearing may have caught Severinus's words. William, sensing danger, ordered Severinus to lock himself in the infirmary and wait, but the herbalist's fate was already sealed.

The Murder and the Weapon

Malachi, driven by Jorge's command to recover the book at all costs, entered the infirmary and killed Severinus with a single, devastating blow from an armillary sphere—a finely crafted astronomical instrument of brass and silver that stood on a table near the door. The sphere, twice the size of a man's head and mounted on a decorated tripod, was smashed against Severinus's skull, shattering its delicate rings and leaving traces of blood, hair, and cerebral matter on the metal. The choice of weapon was both opportunistic and symbolic: it was the nearest heavy object, but its celestial nature also echoed the apocalyptic pattern that Jorge had subtly imposed on the crimes, as the fourth trumpet of the Apocalypse smites a third of the sun, moon, and stars. After the murder, Malachi frantically ransacked the laboratory, overturning shelves and scattering pots, bottles, and books in a desperate search for the forbidden volume, but he was interrupted by the arrival of Remigio of Varagine.

The Arrest of Remigio

Remigio, the cellarer, had been lurking near the infirmary after overhearing William's warning to Severinus. Fearing that the herbalist possessed the incriminating Dolcino letters he had entrusted to Malachi years before, he entered the laboratory only to find Severinus already dead and Malachi gone. As he began his own frantic search, archers sent by Bernard Gui arrived and discovered him amid the devastation. Remigio's protests of innocence were drowned out by the circumstantial evidence: he was found alone with the corpse, his hands covered in the mess of the ransacked room, and his past as a Dolcinian heretic had already been exposed by Salvatore's confession. Bernard Gui, the inquisitor, immediately ordered Remigio's arrest, declaring him guilty of both heresy and murder, and the cellarer was dragged away to face torture and execution. The true killer, Malachi, escaped detection, and the forbidden book—which he had finally seized—was returned to the finis Africae, where it would claim its next victim.

Consequences and the Lost Book

Severinus's death had immediate and far-reaching consequences. It provided Bernard Gui with the pretext he needed to crush the imperial legation's credibility, linking the abbey's crimes to the heretical past of the Dolcinians and, by extension, to the Franciscan Spirituals who shared their ideals of poverty. The murder also removed the one man who might have helped William decipher the book's secrets, as Severinus had been the only person besides Berengar to handle it safely. Most critically, the book itself vanished again: Malachi, after killing Severinus, took it back to the library, and when William and Adso later searched the infirmary, they failed to recognize it because it was bound with an Arabic manuscript and a Syriac alchemical text. The book was only recovered when Benno of Uppsala, the new assistant librarian, retrieved it from his cell and handed it to Malachi, who then died from its poisoned pages. The murder of Severinus thus set in motion the final chain of events that would lead to Jorge's desperate act of destruction and the burning of the library.