Verse 1.1.7

August 12: Here Srila Prabhupada is explaining how Srimad Bhavagavatam is a natural commentary on the Vedanta Sutras. He usually quotes 2 sutras most: Athato brahma jijnasa and Janmadyasya yatah.
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Other sampradayas, there is a commentary on vendata sutras, but in our sampradaya we accept Srimad Bhagavatam as a natural commentary on vedanta sutras. So thats why we do not have any commentary on it.