From Kṛṣṇa, the next expansion is Baladeva, svayaṁ prakāśa. And from Baladeva, there is catur-vyūha: Saṅkarṣaṇa, Aniruddha, Pradyumna. So again there is, from Saṅkarṣaṇa, there is Nārāyaṇa. From Nārāyaṇa, there is another expansion, the same: Saṅkarṣaṇa, Pradyumna, Aniruddha. And from that Saṅkarṣaṇa, there is puruṣāvatāra, Mahā-Viṣṇu. From Mahā-Viṣṇu, there is Garbhodakaśāyī Viṣṇu. From Garbhodakaśāyī Viṣṇu, there is Kṣīrodakaśāyī Viṣṇu. The Kṣīrodakaśāyī Viṣṇu is situated in everyone's heart. Īśvaraḥ sarva-bhūtānāṁ hṛd-deśe 'rjuna tiṣṭhati (BG 18.61).
In this way, Kṛṣṇa is expanding in so many ways: by personal expansion, by the expansion of His energy, by the expansion of His differentiated parts and parcels. Just like we are. We are, we living entities, are vibhinnāṁśa. We are also expansions of Kṛṣṇa. So He is expanding Himself in so many ways: svāṁśa, vibhinnāṁśa and śakti, taṭasthā-śakti, cit-śakti, antaraṅga-śakti, bahiraṅga-śakti. So we have to understand Kṛṣṇa in that way.
And if we study scrutinizingly all this literature, we shall come to the conclusion that Kṛṣṇa is the Supreme Personality of Godhead. And if there is any name of God, that is perfectly given in this word Kṛṣṇa, "all-attractive." There are many derivative meaning of Kṛṣṇa given by the ācāryas, but on the whole, Kṛṣṇa is the actual name of God.
So how you have to . . . for ordinary man, how one can understand Kṛṣṇa, that He is all-pervading? He is all-pervading. He is everywhere. Now, how to appreciate that He is all-pervading? That direction is given by Kṛṣṇa Himself. If we follow the direction of Kṛṣṇa, how to appreciate Him, then naturally and surely we shall come to the point to understand Kṛṣṇa, although He is all-expansive.