Śrīmad-Bhāgavatam · Text 4.12.15
Who is speaking and story frame
मन्यमान इदं विश्वं मायारचितमात्मनि ।
अविद्यारचितस्वप्नगन्धर्वनगरोपमम् ॥ १५ ॥
manyamāna idaṁ viśvaṁ
māyā-racitam ātmani
avidyā-racita-svapna-
gandharva-nagaropamam
Śrīla Dhruva Mahārāja realized that this cosmic manifestation bewilders living entities like a dream or phantasmagoria because it is a creation of the illusory, external energy of the Supreme Lord.
Read Śrīla Prabhupāda's purport on Vedabase.io