In Neopaganism The Horned God Is Seen With Two Different Faces Representing The Duality Of Nature And

In neopaganism the horned god is seen with two different faces representing the duality of nature and the changing of seasonal cycle. The theory of these two aspects of the god was debated by Sir James George Frazer in The Golden Bough and by Robert Graves in The White Goddess.  

According to these theories old religions were fertility cults that revolved around the worship and periodic sacrifice of a sacred king. Frazer based his thesis on the pre-Roman priest-king Rex Nemorensis who was ritually murdered by his successor. The king was the incarnation of a dying and reviving god, a solar deity who underwent a mystic marriage to a goddess of the Earth. He died at the harvest and was reincarnated in the spring. This legend of rebirth is central to almost all of the world's mythologies. Some examples of this archetypical figure are the gods Dionysus, Osiris, Tammuz, Dumuzi, Adonis, Janus, Attis. 

 The two aspects of this figure take the names of Holly and Oak king. 

The Holly King is seen as an old version of the green man, ruler of winter, death and darkness. He starts his kingdom at summer solstice when, after the longest day, ruled by his opposite king the oak king, the days start to get darker and shorter entering in the dark half of the year. The holly king is so called referring to the plant that is fruitful during the winter season.  The holly king is also referred to as a black knight and is also connected with the dark aspects of many pagan gods. 

Counterpart of the Holly King is the Oak King that is usually seen as a young green man, ruler of summer, life and light. He starts his kingdom at the winter solstice, when after the darkest night a new light is reborn, signing the beginning of the light half of the year. The oak king is called over the name of the plant that is fruitful during the hot season. Opposite to the Holly King, the Oak King, relates to the light aspect of many pagan gods and its sometimes referred to as a white knight. 

According to the theory these two kings may be seen as two brothers fighting for the throne or as a father and son passing the kingdom to each other in a perpetual cycle of death and rebirth. This cycle of life and death represents the seasonal cycle of death and rebirth of the sunlight and vegetative world.