When one comes to understand the Supreme Personality of Godhead (vasudevah sarvam iti), when one realizes that Vasudeva is both Paramatma and the impersonal Brahman, he is then in perfect knowledge

Expressions researched:
"when one comes to understand the Supreme Personality of Godhead (vāsudevaḥ sarvam iti), when one realizes that Vāsudeva is both Paramātmā and the impersonal Brahman, he is then in perfect knowledge"

Srimad-Bhagavatam

SB Canto 9

Brahman is a partial representation of Bhagavān, and Vāsudeva, the Supersoul living everywhere and in everyone's heart, is also an advanced realization of the Supreme Personality of Godhead. But when one comes to understand the Supreme Personality of Godhead (vāsudevaḥ sarvam iti), when one realizes that Vāsudeva is both Paramātmā and the impersonal Brahman, he is then in perfect knowledge. Kṛṣṇa is therefore described by Arjuna as paraṁ brahma paraṁ dhāma pavitraṁ paramaṁ bhavān (BG 10.12).

SB 9.9.49, Translation and Purport

The Supreme Personality of Godhead, Vāsudeva, Kṛṣṇa, is extremely difficult to understand for unintelligent men who accept Him as impersonal or void, which He is not. The Lord is therefore understood and sung about by pure devotees.

As stated in Śrīmad-Bhāgavatam (SB 1.2.11):

vadanti tat tattva-vidas

tattvaṁ yaj jñānam advayam

brahmeti paramātmeti

bhagavān iti śabdyate

The Absolute Truth is realized in three phases-as Brahman, Paramātmā and Bhagavān. Bhagavān is the origin of everything. Brahman is a partial representation of Bhagavān, and Vāsudeva, the Supersoul living everywhere and in everyone's heart, is also an advanced realization of the Supreme Personality of Godhead. But when one comes to understand the Supreme Personality of Godhead (vāsudevaḥ sarvam iti), when one realizes that Vāsudeva is both Paramātmā and the impersonal Brahman, he is then in perfect knowledge. Kṛṣṇa is therefore described by Arjuna as paraṁ brahma paraṁ dhāma pavitraṁ paramaṁ bhavān (BG 10.12). The words paraṁ brahma refer to the shelter of the impersonal Brahman and also of the all-pervading Supersoul. When Kṛṣṇa says tyaktvā dehaṁ punar janma naiti mām eti (BG 4.9), this means that the perfect devotee, after perfect realization, returns home, back to Godhead. Mahārāja Khaṭvāṅga accepted the shelter of the Supreme Personality of Godhead, and because of his full surrender he achieved perfection.