SB 2.8.28

prāha bhāgavataṁ nāma
 purāṇaṁ brahma-sammitam
brahmaṇe bhagavat-proktaṁ
 brahma-kalpa upāgate
Synonyms: 
prāha — he said; bhāgavatam — the science of the Personality of Godhead; nāma — of the name; purāṇam — the supplement of the Vedas; brahma-sammitam — just in pursuance of the Vedas; brahmaṇe — unto Lord Brahmā; bhagavat-proktam — was spoken by the Personality of Godhead; brahma-kalpe — the millennium in which Brahmā was first generated; upāgate — just in the beginning.
Translation: 
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.
Purport: 

Śrīmad-Bhāgavatam is the science of the Personality of Godhead. The impersonalist always tries to misrepresent the personal feature of the Lord, not knowing the science of this great knowledge, and Śrīmad-Bhāgavatam is in pursuance of the Vedas and scientific knowledge of the Personality of Godhead. To learn this science one should take shelter of the representative of Śrī Śukadeva and follow in the footsteps of Mahārāja Parīkṣit without foolishly attempting to interpret, thereby committing a great offense at the feet of the Lord. The dangerous ways of interpretations by the nondevotee class of men have played havoc in understanding the Śrīmad-Bhāgavatam, and the careful student should be always alert in this matter if he at all wants to learn the science of Godhead.