The fourth day of the Decameron includes three stories in which young lovers are killed and their bodies are dismembered in some way. Both Ghismonda's lover Guiscardo (IV.1) and Guiglielmo Guardastagno, the lover of Guiglielmo Rossiglione's wife (IV.9), have their hearts cut out by their rivals. The wife of Guiglielmo Rossiglione, in turn, jumps out of a window and is "not only killed ... but almost completely disfigured." At the center of the giornata Lisbetta secretly disinters the head of her murdered lover and places it in a pot of basil over which she weeps for a long time each day (IV.5).
In medieval times the practice of body partition, artistic or actual, was fraught with "ambivalence, controversy, and profound inconsistency." The culture of ancient Rome had possessed strong taboos against moving or dividing corpses, and Christians of the third and fourth centuries maintained this intense concern for proper burial. Indeed, the belief that corporeal integrity is crucial to identity runs throughout medieval culture. The Parisian theologian Gervase of Mt.-St.-Eloi, for example, insisted that it was better to bury bodies intact so they would be "ready for the trumpet" (for the Last Judgment when, it was believed, the soul would be reunited with the body).
Despite these concerns, division of the body for religious purposes was ever more frequently practiced in the thirteenth century as Roman taboos gave way to the Christian cult of relics. By the turn of the century, the practice of dividing the bodies of saints to provide relics (and also the bodies of the nobility to enable them to be buried in several places, near several saints) became widespread. In 1299, however, Boniface legislated against the nobility's practice of dividing bodies for burial, calling it "monstrous and detestable" (although offering no further theological or philosophical justification for his decision).
While the division of the body for religious purposes continued to gain popular support, the dismembering and defiguring of bodies was often carried out for scientific or juridical purposes. In fact, "the use of dismemberment in capital cases makes it clear that it was reserved for only the most repulsive crimes and that the populace was expected to be able to read the nature of the offense from the precise way in which the criminal's body was cut apart and pieces displayed."
Clearly the removal of Guiscardo's and Guiglielmo Guardastagno's hearts was intended to be a punishment in the most horrific sense. The act of physical defilement was intended to "mark" the soul of the deceased, and impede his passage to a peaceful eternity. Lisbetta's detachment and re-burial of her lover's head, on the other hand, speaks to the generative potential of bodily division. The part was taken for the whole. Just as the relic was the saint, so Lorenzo's head was the man himself. If popular belief held that "the heart of a king or the finger of the virgin made the earth where he or she was buried fertile with saintly or royal power," then Lorenzo's head made the basil pot fertile with the power of love.
(C. Si.) Bynum, C. W. Fragmentation and Redemption: Essays on Gender and the Human Body in Medieval Religion. New York: Zone Books, 1991. pp. 265-96.