This is confirmed in Bhagavad-gītā (BG 15.15). Sarvasya cāhaṁ hṛdi sanniviṣṭo mattaḥ smṛtir jñānam apohanaṁ ca. Every living being is controlled by the supreme living being, Paramātmā, who resides within everyone's heart. He is the puruṣa, the puruṣa-avatāra, who creates this material world. The first puruṣa-avatāra is Mahā-Viṣṇu, and that Mahā-Viṣṇu is the plenary portion of the plenary portion of the Supreme Personality of Godhead, Kṛṣṇa. Kṛṣṇa's first expansion is Baladeva, and His next expansions are Vāsudeva, Saṅkarṣaṇa, Aniruddha and Pradyumna. Vāsudeva is the original cause of the brahmajyoti, and the brahmajyoti is the expansion of the rays of the body of Vāsudeva.
- yasya prabhā prabhavato jagad-aṇḍa-koṭi-
- koṭiṣv aśeṣa-vasudhādi-vibhūti-bhinnam
- tad brahma niṣkalam anantam aśeṣa-bhūtaṁ
- govindam ādi-puruṣaṁ tam ahaṁ bhajāmi
"I worship Govinda, the primeval Lord, who is endowed with great power. The glowing effulgence of His transcendental form is the impersonal Brahman, which is absolute, complete and unlimited and which displays the varieties of countless planets, with their different opulences, in millions and millions of universes." (BS 5.40) The Supreme Personality of Godhead is thus described in Bhagavad-gītā:
- mayā tatam idaṁ sarvaṁ
- jagad avyakta-mūrtinā
- mat-sthāni sarva-bhūtāni
- na cāhaṁ teṣv avasthitaḥ
"By Me, in My unmanifested form, this entire universe is pervaded. All beings are in Me, but I am not in them." (BG 9.4)
This is the position of the plenary expansions of Kṛṣṇa as the all-pervading Vāsudeva, Saṅkarṣaṇa, Pradyumna and Aniruddha.