Śrīmad-Bhāgavatam · Text 5.24.3
Who is speaking and story frame
तन्निशम्योभयत्रापि भगवता रक्षणाय प्रयुक्तं सुदर्शनं नाम भागवतं दयितमस्त्रं तत्तेजसा दुर्विषहं मुहु: परिवर्तमानमभ्यवस्थितो मुहूर्तमुद्विजमानश्चकितहृदय आरादेव निवर्तते तदुपरागमिति वदन्ति लोका: ॥ ३ ॥
tan niśamyobhayatrāpi bhagavatā rakṣaṇāya prayuktaṁ sudarśanaṁ nāma bhāgavataṁ dayitam astraṁ tat tejasā durviṣahaṁ muhuḥ parivartamānam abhyavasthito muhūrtam udvijamānaś cakita-hṛdaya ārād eva nivartate tad uparāgam iti vadanti lokāḥ.
After hearing from the sun and moon demigods about Rāhu’s attack, the Supreme Personality of Godhead, Viṣṇu, engages His disc, known as the Sudarśana cakra, to protect them. The Sudarśana cakra is the Lord’s most beloved devotee and is favored by the Lord. The intense heat of its effulgence, meant for killing non-Vaiṣṇavas, is unbearable to Rāhu, and he therefore flees in fear of it. During the time Rāhu disturbs the sun or moon, there occurs what people commonly know as an eclipse.
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