Rāhu, Eclipses, Antarikṣa, and the Seven Subterranean Heavens
Bila-svarga
ततोऽधस्ताद्रसातले दैतेया दानवा: पणयो नाम निवातकवचा: कालेया हिरण्यपुरवासिन इति विबुधप्रत्यनीका उत्पत्त्या महौजसो महासाहसिनो भगवत: सकललोकानुभावस्य हरेरेव तेजसा प्रतिहतबलावलेपा बिलेशया इव वसन्ति ये वै सरमयेन्द्रदूत्या वाग्भिर्मन्त्रवर्णाभिरिन्द्राद्बिभ्यति ॥ ३० ॥
tato ’dhastād rasātale daiteyā dānavāḥ paṇayo nāma nivāta-kavacāḥ kāleyā hiraṇya-puravāsina iti vibudha-pratyanīkā utpattyā mahaujaso mahā-sāhasino bhagavataḥ sakala-lokānubhāvasya harer eva tejasā pratihata-balāvalepā bileśayā iva vasanti ye vai saramayendra-dūtyā vāgbhir mantra-varṇābhir indrād bibhyati.
Below Mahātala lies Rasātala, home of the demoniac sons of Diti and Danu, known as the Paṇis, Nivāta-kavacas, Kāleyas, and the residents of Hiraṇya-pura. Enemies of the devas, they are born mighty and fiercely daring; yet their strength and pride are repeatedly crushed by the splendor of Bhagavān Hari and His Sudarśana cakra, so they dwell in holes like serpents. When Saramā, Indra’s female messenger, utters a mantric curse, they become afraid of Indra.
It is said that there was a great fight between these serpentine demons and Indra, the King of heaven. When the defeated demons met the female messenger Saramā, who was chanting a mantra, they became afraid, and therefore they are living in the planet called Rasātala.
This verse says Rasātala is a subterranean region inhabited by powerful asura groups—Daityas and Dānavas such as the Paṇis, Nivātakavacas, Kāleyas, and the residents of Hiraṇyapura—who live hidden like cave-dwellers.
They fear Indra because his messenger Saramā confronts them with mantra-like speech, and also because their pride is already restrained by the superior potency (tejas) of Lord Hari.
Even great power and boldness become insignificant when opposed to the Supreme Lord’s authority; cultivating humility and taking shelter of Hari is wiser than relying on ego and strength.