A sage in Yudhishtira’s court. There is a story in the Mahabharata that shows the strength of his tapas energy. During their exile, when the Pandavas reached a holy place called Madhugilasamanga, a sage called Lomasha told them this story.

Long ago, in Madhugilasamanga, two sages named Raibhya and Bharadwaja built a hermitage. Bharadwaja had a son named Yavakrita, and Raibhya had two sons named Arvavasu and Paravasu. Yavakrita focused on meditation while Arvavasu and Paravasu focused on knowledge. Yavakrita started meditating to learn things without being taught by brahmins. Indra appeared and told him that this was impossible and he should stop his meditation. Yavakrita refused. Later, Indra approached him as a brahmin while he was bathing in the river. The brahmin tried to build a bridge with the sand grains on the river’s banks. Yavakrita pointed out that it was impossible. Indra told him his meditation was, too. Yavakrita still refused. Finally, Indra gave him the boon. He returned to the hermitage, arrogant and lusted after Raibhya’s daughter-in-law. Raibhya created a rakshasa from his matted locks, and the rakshasa killed Yavakrita. Bharadwaja was shattered by this and  jumped into his son’s pyre after cursing that Raibhya would die at the hands of his own son.

During that time, a brahmin called Brihadyumna conducted a yajna, and invited Arvavasu and Paravasu. As Paravasu was walking through the forest, he saw his father covered up in krishnajina and mistook him for a deer. He killed his own father and confessed to Arvavasu. Arvavasu conducted his father’s last rites in the forest, but Paravasu spread the rumour that Raibhya had been killed by Arvavasu. No one believed Arvavasu, who was dejected. He went into the forest and prayed to Surya. Surya blessed him and Arvavasu revived Raibhya, Bharadwaja and Yavakrita, as per Mahabharata Aranyaparva Chapters 135-138.

As per Mahabharata Shantiparva Chapter 36 verse 7, Arvavasu once had a conversation with Krishna while on his way to Hastinapura.

He is one of the sages whose aura is akin to Rudra, as per Mahabharata Anushasanaparva Chapter 150 verses 30-32.

Arvavasu prayed to Surya for a child. Surya conveyed the Saptamikalpavidhi to Arvavasu and said that if he followed it, he would gain a son and prosperity, as per Bhavishyapurana Brahmaparva.