Śrīmad-Bhāgavatam · Text 2.1.38
Who is speaking and story frame
इयानसावीश्वरविग्रहस्य
य: सन्निवेष: कथितो मया ते ।
सन्धार्यतेऽस्मिन् वपुषि स्थविष्ठे
मन: स्वबुद्ध्या न यतोऽस्ति किञ्चित् ॥ ३८ ॥
iyān asāv īśvara-vigrahasya
yaḥ sanniveśaḥ kathito mayā te
sandhāryate ’smin vapuṣi sthaviṣṭhe
manaḥ sva-buddhyā na yato ’sti kiñcit
I have thus explained to you the gross material gigantic conception of the Personality of Godhead. One who seriously desires liberation concentrates his mind on this form of the Lord, because there is nothing more than this in the material world.
Read Śrīla Prabhupāda's purport on Vedabase.io