Myths, symbolism, and folklore
mistletoe: A plant favored in modern times as a Christmas symbol; in ancient times it was considered sacred in many cultures.
This semiparasitic plant, which draws water and minerals from its host, was considered neither tree nor bush; according to legend, it sprung up where lightning had struck a tree (especially an oak). Mistletoe growing on oak trees was especially prized, e.g., by ancient Romans or the Celtic Druids. According to Pliny the Elder, the Druids cut it with golden sickles, gathered it in a white cloth, and then offered it in sacrifice to the gods, along with a bull.
Mistletoe was considered a panacea, and, because it always remained green, a symbol of immortality. Robert Graves writes that the mistletoe was though to be the sexual organ of the oak tree, and when "the Druids cut it, using a golden sickle for reasons of ritual, they were performing a symbolic castration. The viscous juice of the berries was thought of as the sperm of the oak and a fluid with great powers of rejuvenation."
The English and American custom of hanging up sprigs of mistletoe at Christmas time - and of feeling free to kiss anyone standing under them - seems to go back to the Celtic enthusiasm for the plant.
In Germanic myth, a plot hatched by the wicked Loki turned mistletoe in the hand of the blind god Hod into a lethal spear, which killed Balder, the god of light and vegetation; only after the end of the world (Ragnarok) can Hod and Balder begin a new life in paradise (Gimle). Here the mistletoe symbolizes the innocent tool that becomes an instrument of doom through evil magic, as does the god who throws it, Balder's blind brother. (Biedermann)