Who Brihaspati is
Brihaspati is the priest among the Vedic gods. His other name says what he is: Brahmanaspati, the lord of prayer. The two names take turns inside the same hymn, sometimes inside the same verse. Eleven hymns of the Rigveda are wholly his, and he shares more with Indra.
The poets say he was born from a great light in the highest heaven, and that he drove the darkness away with a sound like thunder. They give him seven mouths and seven rays, a sweet tongue and a clear voice. Red horses pull him. He carries a bow, and its string is truth.
His real weapon is the spoken word. He is the purohita of the gods, the priest who goes in front. One hymn says that without him no sacrifice succeeds, even a wise man's. He speaks the prayer in which the other gods find their home, and he hands prayers on to human priests. A hymn in the tenth book about the beginnings of speech is addressed to him: it remembers the first sages sifting words as flour is sifted through a sieve, and giving things their names.
For that reason his one great story is a priest's story. The cows, and the dawn with them, were shut inside a mountain by Vala. Brihaspati went to the rock with his singing friends, the Angirases, and opened it with a hymn. The same deed is told of Indra, and the two are close friends who drink Soma together. But in Brihaspati's hymns it is the song that breaks the stone.
One of his hymns begins by calling him ganapati, lord of the troop, meaning the band of singers around him. He is also called the father of the gods, and a guardian. He protects the man who prays and punishes the one who hates prayer.
The fourth book draws a human lesson from him. A king who keeps a priest at his side and honours him first will live safely in his own house, it says, and his people will bow to him of their own free will.
When the first sages gave things their names, Brihaspati, that was the earliest speech of all.