Śrīmad-Bhāgavatam · Text 2.8.28
Who is speaking and story frame
प्राह भागवतं नाम पुराणं ब्रह्मसम्मितम् ।
ब्रह्मणे भगवत्प्रोक्तं ब्रह्मकल्प उपागते ॥ २८ ॥
prāha bhāgavataṁ nāma
purāṇaṁ brahma-sammitam
brahmaṇe bhagavat-proktaṁ
brahma-kalpa upāgate
He began to reply to the inquiries of Mahārāja Parīkṣit by saying that the science of the Personality of Godhead was spoken first by the Lord Himself to Brahmā when he was first born. Śrīmad-Bhāgavatam is the supplementary Vedic literature, and it is just in pursuance of the Vedas.
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