Śrīmad-Bhāgavatam · Text 9.14.46
Who is speaking and story frame
तस्य निर्मन्थनाज्जातो जातवेदा विभावसु: ।
त्रय्या स विद्यया राज्ञा पुत्रत्वे कल्पितस्त्रिवृत् ॥ ४६ ॥
tasya nirmanthanāj jāto
jāta-vedā vibhāvasuḥ
trayyā sa vidyayā rājñā
putratve kalpitas tri-vṛt
From Purūravā’s rubbing of the araṇis came a fire. By such a fire one can achieve all success in material enjoyment and be purified in seminal birth, initiation and in the performance of sacrifice, which are invoked with the combined letters a-u-m. Thus the fire was considered the son of King Purūravā.
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