Jon Dathen author of OGHAM (Wisdom of the Trees) writes that Mistletoe rules the 23rd December which is the extra day set apart from the rest of the year due to its sacred and sacrificial nature. There are 13 Ogham months in the calendar year, the last being ruled by the Elder tree, ends on December 22nd. The first month, ruled by the Birch tree starts on the December 24th. Therefore, December 23rd belongs to neither the old or the new year - and gave rise to the old country saying "wait for a year and a day". Mistletoe represents health, return to health, fertility, success, good fortune, a reminder of our responsibilities to others, the need to respect all beings and see ourselves as part of a whole - an individual part of a vast universe encompassing both the spiritual and physical realities (acknowledgement to Jon Dathen).
The plant grows on various trees, particularly the oak and the apple. The ancient British Druids venerated it and traditionally the plant was cut with a golden sickle and used during rites accompanying the sacrifice of a white bull. In mythology mistletoe has a sexual symbolism as it usually grows two berries together - representing testicles. In the classical tradition Uranus was castrated by his son Cronus with a golden sickle. His testicles fell into the sea changing into blood and foam from which rose Aphrodite (Venus) the goddess of love. The twin berries and leaves are also symbolic of the celestial twins. In Scandinavian legend Balder, god of light and son of Odin and Frigga is said to have been slain with an arrow of mistletoe. The plant was dedicated to Frigga, goddess of love - many customs, such as kissing under the mistletoe, would seem to have originated from the belief in its phallic power. In feudal times mistletoe boughs were gathered on Christmas Eve to decorate homes though it was believed to be unlucky to cut the plant before Christmas Eve (acknowledgement to Josephine Addison's The Illustrated Plant Lore).
Mistletoe has come to represent the 'life-force' and life itself as it grows on leafless trees in the midst of winter. At Yuletide it is symbolic of the rebirth of the 'god of light', it is not uncommon for Yule Mistletoe to be saved until Imbolc on February 2nd (Candlemas) to be burned in the fire, thus completing the transition from the winter solstice.
This post is for anyone who finds the number 23 significant in their life (see Cosmic Trigger by Robert Anton Wilson)