Brihaspati (Sk.) The name of a Deity, also of a Rishi. It is like wise the name of the planet Jupiter. He is the personified Guru and priest of the gods in India ; also the symbol of exoteric ritualism as opposed to esoteric mysticism. Hence the opponent of King Soma—the moon, but also the sacred juice drunk at initiation—the parent of Budha, Secret Wisdom.
Source: H.P.Blavatsky - The Theosophical Glossary