The classical conception of love’s arrows were elaborated upon by the Provençal troubadour poets of southern France in the eleventh and twelfth centuries and became part of the European courtly love tradition. In particular, a glimpse of the woman’s eyes was said to be the source of the love dart:
This doctrine of the immediate visual perception of one’s lady as a prerequisite to the birth of love originated among the “beaux esprits” de Provence. […] According to this description, love originates upon the eyes of the lady when encountered by those of her future lover. The love thus generated is conveyed on bright beams of light from her eyes to his, through which it passes to take up its abode in his heart.
In some medieval texts, the gaze of a beautiful woman is compared to the sight of a basilisk¹.
Boccaccio provides one of the most memorable examples in his Il Filostrato, where he mixes the tradition of love at first sight, the eye’s darts, and the metaphor of Cupid’s arrow: “Nor did he (Troilus) who was so wise shortly before… perceive that Love with his darts dwelt within the rays of those lovely eyes… nor notice the arrow that sped to his heart.”
¹ basilisk — a legendary reptile said to have the power to cause death with a single glance.