As the Mahabharata tells it
Mahabharata, Adi Parva, sections 172 and 185 · 3 min read
The five Pandavas were walking north with their mother Kunti. They were in hiding. They walked day and night, and one evening they came to the bank of the Ganga. Arjuna went in front with a burning torch, to light the path and keep wild animals away.
Someone was in the river already. Angaraparna, a king of the Gandharvas, was bathing there with his wives. He heard footsteps on the bank, and he was furious. He bent his bow into a circle.
"Stay back!" he called. "The dusk and the dark belong to the Yakshas, the Gandharvas and the Rakshasas. The rest of the day is for men. Do you not know that I am bathing in this river? I am Angaraparna, friend of Kubera. This forest carries my name. Neither gods nor Yakshas come here."
Arjuna did not stop.
"Who can shut others out of the ocean, or the Himalaya, or this river?" he said. "By day or by night, there is no fixed hour for coming to the Ganga. She flows from the golden peaks to the sea, and she is open to everyone. Why should we not touch her waters?"
The Gandharva answered with arrows. They came like angry snakes. Arjuna turned them aside with his shield and with the torch in his hand.
"Do not try to frighten men who know their weapons," he said. "You Gandharvas are stronger than men. So I will not fight you with tricks. I will use a weapon of the gods."
He threw the weapon of fire that his teacher Drona had given him. It burned the Gandharva's chariot in a moment. Angaraparna fell from it head first, stunned. Arjuna caught him by his hair, which was wound with flower garlands, and dragged him towards his brothers.
A woman ran out of the dark. She went straight to Yudhishthira.
"Protect me! Set my husband free! I am Kumbhinasi, his wife."
Yudhishthira looked at Arjuna.
"Who would kill an enemy who has been beaten, who has lost his fame, and whom a woman is protecting? Let him go."
"Keep your life, Gandharva," said Arjuna. "Go, and do not grieve. The king of the Kurus commands me to show you mercy."
The Gandharva stood up. He spoke differently now.
"I have been beaten, so I give up my proud name," he said. "I was called after my bright chariot. Let me be called after my burnt one. And let me give something to the man who gave me my life."
He offered Arjuna a science of seeing called Chakshushi, by which a person may see whatever he wishes to see. Manu had taught it to Soma, he said, Soma to Vishvavasu, and Vishvavasu to him. He offered each brother a hundred horses bred in the Gandharva country, which never tire and can go anywhere.
"I will not take a gift for sparing a life," said Arjuna.
"Then let it be a trade between friends. Give me your weapon of fire."
"For the horses, I will. Let our friendship last. But tell me this. We are honest men who know the Veda. Why did you threaten us?"
The Gandharva's answer was plain. "You have no wives. You have not yet set up a household. And no priest walks in front of you. At night our strength grows, and I was angry before my wife. You beat me because you are living as a student lives, in strict discipline. But a king needs a priest. Find one, and you will win back the earth."
"Then name one," said Arjuna.
"There is a shrine in these woods called Utkochaka. Dhaumya, the younger brother of Devala, lives there in discipline. Choose him."
Arjuna gave him the fire weapon with the proper rites. The horses he left in the Gandharva's keeping until the day they were needed. Then the brothers went to Utkochaka, and Dhaumya became their priest.