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:,मातले! फेनका आहार करनेके कारण वे महर्षिगण “फेनप” नामसे विख्यात हैं। वे बड़ी कठोर तपस्यामें संलग्न रहते हैं। उनसे देवतालोग भी डरते हैं
phenapā nāma te khyātāḥ phenāhārāśn māṭale | ugre tapasi vartante yeṣāṃ bibhyati devatāḥ ||
Wahai Mātali, para resi itu dikenal dengan nama Phenapā karena mereka menjadikan buih sebagai santapan. Mereka menempuh tapa yang amat keras; sedemikian dahsyat disiplin mereka hingga para dewa pun menaruh gentar.
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.