Nārada Muni, after offering respects to Nārāyaṇa Ṛṣi, went to the āśrama of Vyāsadeva, his disciple. Being properly received by Vyāsadeva in his āśrama and seated very comfortably, Nārada Muni narrated the entire story of what he had heard from Nārāyaṇa Ṛṣi. In this way Śukadeva Gosvāmī informed Mahārāja Parīkṣit of the answers to his questions regarding the essence of Vedic knowledge and what is considered to be the ultimate goal in the Vedas. The supreme goal of life is to achieve the transcendental blessings of the Supreme Personality of Godhead and thus become engaged in the loving service of the Lord. One should follow in the footsteps of Śukadeva Gosvāmī and all the other Vaiṣṇavas in the disciplic succession and should pay respectful obeisances unto Lord Kṛṣṇa, the Supreme Personality of Godhead, Hari. The four sects of Vaiṣṇava disciplic succession, namely the Madhva-sampradāya, the Rāmānuja-sampradāya, the Viṣṇu-svāmi-sampradāya and the Nimbārka-sampradāya, in pursuance of all Vedic conclusions, agree that one should surrender unto the Supreme Personality of Godhead.
The Vedic literature is divided into two parts: the śrutis and the smṛtis. The śrutis are the four Vedas—Ṛg, Sāma, Atharva and Yajur—and the Upaniṣads, and the smṛtis are the Purāṇas and the Itihāsas like the Mahābhārata, which includes the Bhagavad-gītā. The conclusion of all these is that one should know Śrī Kṛṣṇa as the Supreme Personality of Godhead. He is the Parama-puruṣa, or the Supreme Personality of Godhead, under whose superintendence material nature works. For creation, maintenance and annihilation, the Supreme Lord incarnates into three—Lord Brahmā, Lord Viṣṇu and Lord Śiva—after manifesting the material cosmos. All of these take charge of the three modes of material nature, but the ultimate direction is in the hand of Lord Viṣṇu. The complete activities of material nature under the three modes are conducted under the direction of the Supreme Personality of Godhead, Kṛṣṇa. This is confirmed in the Bhagavad-gītā (mayādhyakṣeṇa (BG 9.10)) and in the Vedas (sa aikṣata).
The atheistic Sāṅkhyaite philosophers will of course offer their arguments that the material cosmic manifestation is due to prakṛti and puruṣa—material nature and the living entity, or the material cause and the effective cause. But Kṛṣṇa is the cause of all causes. He is the cause of both the material and the effective causes. Prakṛti and puruṣa are not the ultimate cause. Superficially it appears that a child is born due to the combination of the father and mother, but the ultimate cause of both the father and the mother is Kṛṣṇa. He is therefore the original cause, or the cause of all causes, as confirmed in the Brahma-saṁhitā.
Both the Supreme Lord and the living entities enter into the material nature. The Supreme Lord, Kṛṣṇa, by one of His plenary expansions, manifests as Kāraṇodakaśāyī, Mahā-Viṣṇu, the gigantic Viṣṇu form lying in the Causal Ocean. Then from that gigantic form of Mahā-Viṣṇu, Garbhodakaśāyī Viṣṇu expands and enters into every universe. From Him, Brahmā, Viṣṇu and Śiva expand. Viṣṇu as Kṣīrodakaśāyī enters into the hearts of all living entities, as well as into all material elements, including the atom. The Brahma-saṁhitā says, aṇḍāntara-stha-paramāṇu-cayāntara-stham: (BS 5.35) “The Lord is within this universe and also within every atom.”