Chandogya Upanishad 4.2

tad u ha jānaśrutiḥ pautrāyaṇaḥ ṣaṭ śatāni gavāṃ niṣkam aśvatarīrathaṃ tad ādāya praticakrame taṃ hābhyuvāda

Then Gânasruti Pautrâyana took six hundred cows, a necklace, and a carriage with mules, went to Raikva and said:

raikvemāni ṣaṭ śatāni gavām ayaṃ niṣko 'yam aśvatarīrathaḥ anu ma etāṃ bhagavo devatāṃ śādhi yāṃ devatām upāssa iti

'Raikva, here are six hundred cows, a necklace, and a carriage with mules; teach me the deity which you worship.'

tam u ha paraḥ pratyuvācāha hāretvā śūdra tavaiva saha gobhir astv iti tad u ha punar eva jānaśrutiḥ pautrāyaṇaḥ sahasraṃ gavāṃ niṣkam aśvatarīrathaṃ duhitaraṃ tad ādāya praticakrame

The other replied: 'Fie, necklace and carriage be thine, O Sûdra, together with the cows.' Then Gânasruti Pautrâyana took again a thousand cows, a necklace, a carriage with mules, and his own daughter, and went to him.

taṃ hābhyuvāda raikvedaṃ sahasraṃ gavām ayaṃ niṣko 'yam aśvatarīratha iyaṃ jāyāyaṃ grāmo yasminn āsse 'nv eva mā bhagavaḥ śādhīti

He said to him: 'Raikva, there are a thousand cows, a necklace, a carriage with mules, this wife, and this village in which thou dwellest. Sir, teach me!'

tasyā ha mukham upodgṛhṇann uvācājahāremāḥ śūdrānenaiva mukhenālāpayiṣyathā iti te haite raikvaparṇā nāma mahāvṛṣeṣu yatrāsmā uvāsa tasmai hovāca

He, opening her mouth, said: 'You have brought these (cows and other presents), O Sûdra, but only by that mouth did you make me speak.' These are the Raikva-parana villages in the country of the Mahâvrishas (mahâpunyas) where Raikva dwelt under him. And he said to him: