SB 9.9.49
yat tad brahma param suksmam
asunyam sunya-kalpitam
bhagavan vasudeveti
yam grnanti hi satvatah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Personality of Godhead, Vasudeva, Krsna, 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.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As stated in Srimad-Bhagavatam (1.2.11):
vadanti tat tattva-vidas
tattvam yaj jñanam advayam
brahmeti paramatmeti
bhagavan iti sabdyate
The Absolute Truth is realized in three phases — as Brahman, Paramatma and Bhagavan. Bhagavan is the origin of everything. Brahman is a partial representation of Bhagavan, and Vasudeva, 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 (vasudevah sarvam iti), when one realizes that Vasudeva is both Paramatma and the impersonal Brahman, he is then in perfect knowledge. Krsna is therefore described by Arjuna as param brahma param dhama pavitram paramam bhavan. The words param brahma refer to the shelter of the impersonal Brahman and also of the all-pervading Supersoul. When Krsna says tyaktva deham punar janma naiti mam eti, this means that the perfect devotee, after perfect realization, returns home, back to Godhead. Maharaja Khatvanga accepted the shelter of the Supreme Personality of Godhead, and because of his full surrender he achieved perfection.
Thus end the Bhaktivedanta purports of the Ninth Canto, Ninth Chapter, of the Srimad-Bhagavatam, entitled “The Dynasty of Amsuman.”