The heart has a long and complex history as a powerful symbol in both Christian iconography and popular usage. The Cult of the Sacred Heart, which symbolises Jesus’s love for mankind, had its origins in early Christianity and was popularised by St. Francis of Assisi in the early thirteenth century. The sacred heart was often depicted pierced by an arrow or spear or wearing a crown of thorns, which was meant to represent Christ’s sacrifice for and at the hands of humankind. The pierced heart was also associated with St. Augustine, whose followers had integrated the icon into their insignia.

The symbol of the heart pierced with an arrow was also linked to carnal love, often in the context of being lovestruck or infatuated by someone else. This usage of the symbol predates Christianity and came from the mythology surrounding Cupid, the Roman god of love and desire. Knowledge of Cupid never totally disappeared from Europe, but it was renewed in the twelfth century with the rediscovery of ancient texts translated from Arabic. This period was characterized by a search for knowledge and a demand for ancient sources, which was driven by the rise of universities, as well as the diminishing influence of the Muslim scholars of the declining Al-Andalus (Muslim Iberia). By the thirteenth century, negative connotations had become associated with Cupid that linked his imagery to sinful love. Like many pagan deities, he became feared and associated with demons, particularly the Devil himself, due to his connection with lust. 

As seen in the picture below, the image of the heart pierced by an arrow was incorporated into the designs adorning the leather binding of Hemmerlin's Opuscula et tractatus. Considering the context surrounding the publication of Opuscula et tractatus and the content of Hemmerlin’s writings, the usage of this iconography was likely intended to convey connotations of sinful love. Indeed, Hemmerlin wrote about spells that were used in order to possess lovers with the help of wax figures. The usage of the heart pierced with an arrow as a symbol of uncontrollable worldly lustful desires is not surprising considering that the target of most witch-trials in the fifteenth century were women and that the crimes that they were accused of were typically linked to the use of spells to control men, most often with magic that influenced lust and reproductivity.