Bhāgavata is the natural commentary on the Vedānta-sūtra. Therefore one who has sufficient knowledge in Bhāgavata, he has automatically sufficient knowledge in Vedānta-sūtra. According to Vedic system, one must have sufficient knowledge in Vedānta-sūtra. Then he'll be considered as learned in spiritual science.
So Śrīmad-Bhāgavatam, although the Vaiṣṇavas, they have got their commentaries on Vedānta-sūtra, but this Caitanya Mahāprabhu's sampradāya, they did not make any commentary on the Vedānta-sūtra because they belonged to the disciplic succession of Vyāsadeva. So Vyāsadeva is the spiritual master. So the later ācārya, they did not think it proper that whatever the . . .
Because their spiritual master has had already made a commentary on the Vedānta-sūtra, "Oh, that is sufficient. Why should we do again?" These are some of the etiquettes. Anyway, the Vedānta-sūtra . . . and Bhāgavata is natural commentary on Vedānta-sūtra, and Lord Caitanya therefore gives evidence from the Bhāgavata generally, and Purāṇas also, Mahābhārata and anyway, I mean to say, Upaniṣad. They are all authorities. But especially He gives evidences from Śrīmad-Bhāgavatam.