Swayamprakasha Yogindra Charitam Vol III Book X Chp 12 Shlokas 1 - 5
श्रीसद्गुरुरुवाच
श्रुतिस्मृतिपुराणानां सारभूतमिदं कलौ |
श्रीमद्भागवतं शास्त्रं व्यासपुत्रेण कीर्तितम् ||
किं वृथाsन्यैः पुराणैस्तु बुद्धिमोहविधायकैः |
एकं भागवतं शास्त्रं तत्वज्ञानप्रदायकम् ||
अलं भागवतं शास्त्रं वेत्तुं भगवतो गुणान् |
गुणान् भागवानाञ्च वेत्तुं वैष्णवसंहिता ||
रामायणं भारतञ्च पुराणानीतराणि च |
श्रीमद्भागवते शास्त्रे वर्तन्ते व्तक्तमेव हि ||
कलिकालोचितं शास्त्रं श्रीमद्भागवतं परम् |
कथयन् कृष्णभक्तिञ्च स्थापयेद्भुवि वैष्णवः ||
Shri Sadguru said
The great Shastra, Shastri, Shrimp Bhagavatam, which is the essence of Sruti, Smriti and the Puranas was rendered by Shri Shula in the Kaliyuga. What is the use of so many other Puranas that make the mind get illusion? Only the Bhagavata Shastri is capable of imparting knowledge of the secret tats. A deep study of the Bhagavata Shastri is enough to know the attributes of Shri Bhagavam. Similarly reading the Vaishnava Samhita is enough to get acquainted with the attributes of the bhagavatas. The Ramayana, the Mahabharata and other Puranas are explicit parts of the Bhagavata Purana. The bhagavatas could establish Krishna Bhakti among the people spreading gospels of SHrimad Bhagavatam which is the Shastras best suited to Kaliyuga.