Udyoga Parva, Adhyāya 101: Bhogavatī-varṇana, Nāga-vaṃśa-kathana, and Sumukha-vivāha-prastāva
फेनपा नाम ते ख्याता: फेनाहाराश्न मातले । उग्रे तपसि वर्तन्ते येषां बिभ्यति देवता:
phenapā nāma te khyātāḥ phenāhārāśn māṭale | ugre tapasi vartante yeṣāṃ bibhyati devatāḥ ||
О Матали, те мудрецы известны под именем Фенапа (Phenapā), ибо питаются пеной. Они пребывают в чрезвычайно суровой тапасе; столь велика мощь их подвига, что даже боги взирают на них с благоговейным страхом.
नारद उवाच
Extreme self-restraint and disciplined tapas are portrayed as generating profound spiritual potency—so formidable that even divine beings regard such ascetics with awe. The verse underscores the ethical ideal that inner mastery can surpass worldly status.
Nārada informs Mātali about a group of sages called the Phenapāḥ, explaining their distinctive austerity—living on foam—and emphasizing the severity of their practice and the reverence (even fear) it inspires among the gods.