Mahabharata 1.32.2

1.32.2

sūta uvāca |
teṣāṃ tu bhagavāñśeṣastyaktvā kadrūṃ mahāyaśāḥ |
tapo vipulamātasthe vāyubhakṣo yatavrataḥ || 2 ||

"Sauti said, 'The illustrious Sesha amongst them, of great renown, leaving his mother practised hard penances, living upon air and rigidly observing his vows. He practised these ascetic devotions, repairing to Gandhamadana, Vadri, Gokarna, the woods of Pushkara, and the foot of Himavat. And he passed his days in those sacred regions, some of which were sacred for their water and others for their soil in the rigid observance of his vows, with singleness of aim, and his passions under complete control. And the Grandsire of all, Brahma, saw that ascetic with knotted hair, clad in rags, and his flesh, skin, and sinews dried up owing to the hard penances he was practising. And the Grandsire addressing him, that penance-practising one of great fortitude, said, 'What is that thorn doest, O Sesha? Let the welfare of the creatures of the worlds also engage thy thoughts. O sinless one, thou art afflicting all creatures by thy hard penances. O Sesha, tell me the desire implanted in thy breast.'