सान्दीपनि
Sandipani is the teacher of Krishna and Balarama. In the third Skandha Uddhava tells Vidura that Krishna learned from him the whole Veda, told once, with its elaboration, and as his fee recovered his dead son — who lay in the belly of the asura Pancajana — and gave him back: 'sAndIpaneH sakR^it-proktaM brahma adhItya savistaram / tasmai prAdAd varaM putraM mR^itaM pa~nchajanodarAt' (SB 3.3.2). 'sakR^it-proktam', told once, is the measure of the feat.
Śrīmad Bhāgavata Mahāpurāṇa 3.3.2 — Sanskrit Wikisource (pinned chapter page; Devanagari from the cross-validated transcription in validation/sanskrit_skandha3.json)
Krishna learned from Sandipani the whole Veda, told once, with its elaboration, and gave back in return his dead son, taken from the belly of Pancajana: 'sAndIpaneH sakR^it-proktaM brahma adhItya savistaram' (SB 3.3.2).
