Śrīmad-Bhāgavatam · Text 2.6.42
Who is speaking and story frame
आद्योऽवतार: पुरुष: परस्य
काल: स्वभाव: सदसन्मनश्च ।
द्रव्यं विकारो गुण इन्द्रियाणि
विराट् स्वराट् स्थास्नु चरिष्णु भूम्न: ॥ ४२ ॥
ādyo ’vatāraḥ puruṣaḥ parasya
kālaḥ svabhāvaḥ sad-asan-manaś ca
dravyaṁ vikāro guṇa indriyāṇi
virāṭ svarāṭ sthāsnu cariṣṇu bhūmnaḥ
Kāraṇārṇavaśāyī Viṣṇu is the first incarnation of the Supreme Lord, and He is the master of eternal time, space, cause and effects, mind, the elements, the material ego, the modes of nature, the senses, the universal form of the Lord, Garbhodakaśāyī Viṣṇu, and the sum total of all living beings, both moving and nonmoving.
Read Śrīla Prabhupāda's purport on Vedabase.io