Mahabharata 1.3.58

1.3.58

tamupādhyāyaḥ pratyuvāca |
aśvinau stuhi |
tau tvāṃ cakṣuṣmantaṃ kariṣyato devabhiṣajāviti || 58 ||

"The preceptor then said, 'Upamanyu being restrained by me from the use of everything, is, of course, and therefore, doth not come home until it be late. Let us then go in search of him.' And having said this, he went with his disciples into the forest and began to shout, saying, 'Ho Upamanyu, where art thou?' And Upamanyu hearing his preceptor's voice answered in a loud tone, 'Here I am at the bottom of a well.' And his preceptor asked him how he happened to be there. And Upamanyu replied, 'Having eaten of the leaves of the Arka plant I became blind, and so have I fallen into this well.' And his preceptor thereupon told him, 'Glorify the twin Aswins, the joint physicians of the gods, and they will restore thee thy sight.' And Upamanyu thus directed by his preceptor began to glorify the twin Aswins, in the following words of the Rig Veda: