SB 12.6.4

purāṇa-saṁhitām etām
 aśrauṣma bhavato vayam
yasyāṁ khalūttamaḥ-śloko
 bhagavān anuvarṇyate
Synonyms: 
purāṇa-saṁhitām — essential summary of all the Purāṇas; etām — this; aśrauṣma — have heard; bhavataḥ — from you; vayam — we; yasyām — in which; khalu — indeed; uttamaḥ-ślokaḥ — who is always described in choice poetry; bhagavān — the Personality of Godhead; anuvarṇyate — is fittingly described.
Translation: 
I have heard from you this Śrīmad-Bhāgavatam, which is the perfect summary of all the Purāṇas and which perfectly describes the Supreme Lord, Uttamaḥśloka.