Mahabharata Anushasna Parva Chapter 150:2

Mahabharata Anushasna Parva (Dana Dharma Parva) Chapter 150:2 Those lords among the deities behold everything although they are invisible. Indeed, they behold all the good and bad acts of all beings. They are Mrityu, Kala, the Viswedevas, the Pitris endued with forms, the great Rishis possessed of wealth of penances, the Munis, and others crowned with success and devoted to penances and emancipation. These of sweet smiles, bestow diverse benefits upon those men that recite their names. Verily, endued with celestial energy, they bestow diverse regions of felicity created by the Grandsire upon such men. They reside in all the worlds and attentively note all acts. By reciting the names of those lords of all living creatures, one always becomes endued with righteousness and wealth and enjoyments in copious measure. One acquires hereafter diverse regions of auspiciousness and felicity created by the Lord of the universe. These three and thirty deities, who are the lords of all beings as also Nandiswara of huge body, and that pre-eminent one who has the bull for the device on his banner, and those masters of all the worlds, viz., the followers and associates of him called Ganeswara, and those called Saumyas, and called the Rudras, and those called the Yogas, and those that are known as the Bhutas, and the luminaries in the firmament, the Rivers, the sky, the prince of birds (viz., Garuda), all those persons on earth who have become crowned with success in consequence of their penances and who are existing in an immobile or mobile form, the Himavat, all the mountains, the four Oceans, the followers and associates of Bhava who are possessed of prowess equal to that of Bhava himself, the illustrious and ever-victorious Vishnu, and Skanda, and Ambika,—these are the great souls by reciting whose name with restrained senses, one becomes cleansed of all sins. After this I shall recite the names of those foremost Rishis who are known as Manavas. They are Yavakrita, and Raibhya, and Arvavasu, and Paravasu, and Aushija, and Kakshivat, and Vala the son of Angiras. Then comes Kanwa the son of the Rishi Medhatithi, and Varishada. All these are endued with the energy of Brahma and have been spoken of (in the scriptures) as creators of the universe. They have sprung from Rudra and Anala and the Vasus. By reciting their names people obtain great benefits. Indeed, by doing good deeds on earth, people sport in joy in heaven, with the deities. These Rishis are the priests of Indra. They live in the east. That man who, with rapt attention, recites the names of these Rishis, succeeds in ascending to the regions of Indra and obtaining great honours there. Unmachu, Pramchu, Swastyatreya of great energy, Dridhavya, Urdhvavahu, Trinasoma, Angiras, and Agastya of great energy, the son of Mitravaruna,—these seven are the Ritwiks of Yama the king of the dead, and dwell in the southern quarter. Dridheyu and Riteyu, and Pariyadha of great fame, and Ekata, and Dwita, and Trita—the last three endued with splendour like that of the sun,—and Atri's son of righteous soul, viz., the Rishi Saraswata,—these seven who had acted as Ritwiks in the great sacrifice of Varuna—have taken up their abodes in the western quarter.