When Brahmā saw this mystic power of Lord Kṛṣṇa's, he admitted defeat and offered prayers to the Lord, addressing Him as the proprietor and seer of everything in the creation and as the Supersoul who is within each and every living entity and is dear to all. That Lord Kṛṣṇa is Nārāyaṇa, the father of Brahmā, because Lord Kṛṣṇa's plenary expansion Garbhodakaśāyī Viṣṇu, after placing Himself on the Garbha Ocean, created Brahmā from His own body. Mahā-Viṣṇu in the Causal Ocean and Kṣīrodakaśāyī Viṣṇu, the Supersoul in everyone's heart, are also transcendental expansions of the Supreme Truth.
(Sri Caitanya Caritamrta------1:2:30------purport).

Thus the Lord's incarnations were enumerated, including Matsya, the fish incarnation; Kūrma, the tortoise; Lord Rāmacandra; Nṛsiṁhadeva; Vāmanadeva; and Varāha, the boar incarnation. Thus there are innumerable līlā-avatāras, and all of these exhibit wonderful pastimes. Lord Varāha, the boar incarnation, lifted the entire planet earth from the depths of the Garbhodaka Ocean. The tortoise incarnation, Lord Kūrma, became a pivot for the emulsification of the whole sea, and Lord Nṛsiṁhadeva appeared as half-man, half-lion. These are some of the wonderful and uncommon features of līlā-avatāras.
(Sri Caitanya Caritamrta------2:6:99------purport).

This is a quotation from Śrīmad-Bhāgavatam (3.9.3). This verse was spoken by Lord Brahmā, who perfectly realized the Supreme Personality of Godhead after meditating upon the Lord within the water of the Garbhodaka Ocean. Brahmā realized that the form of the Lord is completely spiritual. This is certainly a better understanding of the Absolute Truth than the impersonal understanding.
(Sri Caitanya Caritamrta------2:25:36------purport).

Lord Brahmā said: When the unlimitedly powerful Lord assumed the form of a boar as a pastime, just to lift the planet earth, which was drowned in the great ocean of the universe called the Garbhodaka, the first demon (Hiraṇyākṣa) appeared, and the Lord pierced him with His tusk."
(Srimad Bhagavatam------2:7:1------purport).

Since the beginning of creation, the demons and the demigods, or the Vaiṣṇavas, are always the two classes of living beings to dominate the planets of the universes. Lord Brahmā is the first demigod, and Hiraṇyākṣa is the first demon in this universe. Only under certain conditions do the planets float as weightless balls in the air, and as soon as these conditions are disturbed, the planets may fall down in the Garbhodaka Ocean, which covers half the universe. The other half is the spherical dome within which the innumerable planetary systems exist. The floating of the planets in the weightless air is due to the inner constitution of the globes, and the modernized drilling of the earth to exploit oil from within is a sort of disturbance by the modern demons and can result in a greatly harmful reaction to the floating condition of the earth. A similar disturbance was created formerly by the demons headed by Hiraṇyākṣa (the great exploiter of the gold rush), and the earth was detached from its weightless condition and fell down into the Garbhodaka Ocean. The Lord, as maintainer of the whole creation of the material world, therefore assumed the gigantic form of a boar with a proportionate snout and picked up the earth from within the water of Garbhodaka.
(Srimad Bhagavatam------2:7:1------purport).

The word rasāyām is sometimes interpreted to mean Rasātala, the lowest planetary system, but that is not applicable in this connection, according to Viśvanātha Cakravartī Ṭhākura. The earth is seven times superior to the other planetary systems, namely Tala, Atala, Talātala, Vitala, Rasātala, Pātāla, etc. Therefore the earth cannot be situated in the Rasātala planetary system. It is described in the Viṣṇu-dharma:
pātāla-mūleśvara-bhoga-saṁhatau
vinyasya pādau pṛthivīṁ ca bibhrataḥ
yasyopamāno na babhūva so 'cyuto
mamāstu māṅgalya-vivṛddhaye hariḥ
Therefore the Lord found the earth on the bottom of the Garbhodaka Ocean, where the planets rest during the devastation at the end of Brahmā's day.
(Srimad Bhagavatam------3:13:30------purport).

The Lord is spoken of herewith as the origin of the boar species. As stated in the Vedānta-sūtra (1.1.2), the Absolute Truth is the origin of everything. Therefore it is to be understood that all 8,400,000 species of bodily forms originate from the Lord, who is always ādi, or the beginning. In Bhagavad-gītā Arjuna addresses the Lord as ādyam, or the original. Similarly, in the Brahma-saṁhitā the Lord is addressed as ādi-puruṣam, the original person. Indeed, in Bhagavad-gītā (10.8) the Lord Himself declares, mattaḥ sarvaṁ pravartate: "From Me everything proceeds."
In this situation the Lord assumed the shape of a boar to kill the demon Hiraṇyākṣa and pick up the earth from the Garbha Ocean. Thus He became ādi-sūkara, the original boar.
(Srimad Bhagavatam------3:19:31------purport).

When that Supreme Personality of Godhead who is lying on the Garbhodaka Ocean entered the heart of Brahmā, Brahmā brought his intelligence to bear, and with the intelligence invoked he began to create the universe as it was before."
(Srimad Bhagavatam------3:20:17------purport).

Brahmā is the appointed lord of the universe. Because his father is Garbhodakaśāyī Viṣṇu, Lakṣmī, the goddess of fortune, is automatically his mother. Lakṣmījī is worshiped by all demigods and by the inhabitants of other planets as well. Human beings are also eager to receive favor from the goddess of fortune. Lakṣmī is always engaged in massaging the legs and thighs of the Supreme Personality of Godhead Nārāyaṇa, who is lying on the ocean of Garbha within the universe. Brahmā is described here as the son of the goddess of fortune, but actually he was not born of her womb. Brahmā takes his birth from the abdomen of the Lord Himself. A lotus flower grows from the abdomen of Garbhodakaśāyī Viṣṇu, and Brahmā is born there.
(Srimad Bhagavatam------3:28:23------purport).

There are two kinds of dissolutions. One dissolution takes place at the end of the life of Brahmā. At that time all the planetary systems, including the heavenly systems, are dissolved in water and enter into the body of Garbhodakaśāyī Viṣṇu, who lies on the Garbhodaka Ocean on the bed of serpents, called Śeṣa. In the other dissolution, which occurs at the end of Brahmā's day, all the lower planetary systems are destroyed. When Lord Brahmā rises after his night, these lower planetary systems are again created.
(Srimad Bhagavatam------3:32:4------purport).

The earth informed King Pṛthu that if he destroyed her, he and his subjects would all fall down into the waters of the garbha ocean. King Pṛthu now replies to that point. Although the earth assumed the shape of a cow by her mystic powers in order to be saved from being killed by the King, the King was aware of this fact and would not hesitate to cut her to pieces, just like small bits of grain.
(Srimad Bhagavatam------4:17:27------purport).

This refers to the time when Lord Kṛṣṇa appeared as the supreme boar, Varāha, and rescued the earth, which had been merged in water. The asura Hiraṇyākṣa had dislocated the earth from its orbit and thrown it beneath the waters of the Garbhodaka Ocean. Then the Lord, in the shape of the original boar, rescued the earth.
(Srimad Bhagavatam------4:17:34------purport).

The Lord as Garbhodakaśāyī Viṣṇu lies in the ocean of Garbha within this universe, and from His navel the lotus flower sprouts. Lord Brahmā is generated from that lotus flower, and from Lord Brahmā the creation of this material world begins. As such, the Supreme Personality of Godhead, Garbhodakaśāyī Viṣṇu, is the origin of the material senses and sense objects.
(Srimad Bhagavatam------4:24:34------purport).

My Lord, as the original boar within this universe, You fought and killed the great demon Hiraṇyakṣa. Then You lifted me (the earth) from the Garbhodaka Ocean on the end of Your tusk, exactly as a sporting elephant plucks a lotus flower from the water. I bow down before You."
(Srimad Bhagavatam------5:18:39------purport).

Śrīla Jīva Gosvāmī has translated this verse as follows. "The Supreme Personality of Godhead is the cause of all causes. It is by His will that gross and subtle ingredients interact. He appears in various incarnations just to please the hearts of His pure devotees." For example, the Supreme Lord appeared in the transcendental incarnation of Lord Varāha (the boar) just to please His devotees by lifting the planet earth from the Garbhodaka Ocean.
(Srimad Bhagavatam------5:25:10------purport).

Śrīla Viśvanātha Cakravartī Ṭhākura explains that the different hellish planets within this universe are held slightly above the Garbhodaka Ocean and remain situated there. This chapter describes how all sinful persons go to these hellish planets and how they are punished there by the assistants of Yamarāja. Different individuals with different bodily features enjoy or suffer various reactions according to their past deeds.
(Srimad Bhagavatam------5:26:1------purport).

The great sage Śukadeva Gosvāmī answered: All the hellish planets are situated in the intermediate space between the three worlds and the Garbhodaka Ocean. They lie on the southern side of the universe, beneath Bhū-maṇḍala, and slightly above the water of the Garbhodaka Ocean. Pitṛloka is also located in this region between the Garbhodaka Ocean and the lower planetary systems. All the residents of Pitṛloka, headed by Agniṣvāttā, meditate in great samādhi on the Supreme Personality of Godhead and always wish their families well."
As previously explained, below our planetary system are seven lower planetary systems, the lowest of which is called Pātālaloka. Beneath Pātālaloka are other planets, known as Narakaloka, or the hellish planets. At the bottom of the universe lies the Garbhodaka Ocean. Therefore the hellish planets lie between Pātālaloka and the Garbhodaka Ocean.
(Srimad Bhagavatam------5:26:5------purport).

Yamarāja is not a fictitious or mythological character; he has his own abode, Pitṛloka, of which he is king. Agnostics may not believe in hell, but Śukadeva Gosvāmī affirms the existence of the Naraka planets, which lie between the Garbhodaka Ocean and Pātālaloka. Yamarāja is appointed by the Supreme Personality of Godhead to see that the human beings do not violate His rules and regulations.
(Srimad Bhagavatam------5:26:6------purport).

Appearing as Nṛsiṁhadeva, the Supreme Personality of Godhead, Śrī Hari, killed Hiraṇyakaśipu. When the Lord delivered the planet earth, which had fallen in the Garbhodaka Ocean, Hiraṇyākṣa tried to hinder Him, and then the Lord, as Varāha, killed Hiraṇyākṣa."
(Srimad Bhagavatam------7:1:41------purport).

Summarizing the entire description of the planetary systems of the universe, Śrīla Viśvanātha Cakravartī Ṭhākura says that one who is able to meditate upon this arrangement as the virāṭ-rūpa, or viśva-rūpa, the external body of the Supreme Personality of Godhead, and worship Him three times a day by meditation will always be free from all sinful reactions. Viśvanātha Cakravartī Ṭhākura estimates that Dhruvaloka, the polestar, is 3,800,000 yojanas above the sun. Above Dhruvaloka by 10,000,000 yojanas is Maharloka, above Maharloka by 20,000,000 yojanas is Janaloka, above Janaloka by 80,000,000 yojanas is Tapoloka, and above Tapoloka by 120,000,000 yojanas is Satyaloka. Thus the distance from the sun to Satyaloka is 233,800,000 yojanas, or 1,870,400,000 miles. The Vaikuṇṭha planets begin 26,200,000 yojanas (209,600,000 miles) above Satyaloka. Thus the Viṣṇu Purāṇa describes that the covering of the universe is 260,000,000 yojanas (2,080,000,000 miles) away from the sun. The distance from the sun to the earth is 100,000 yojanas, and below the earth by 70,000 yojanas are the seven lower planetary systems called Atala, Vitala, Sutala, Talātala, Mahātala, Rasātala and Pātāla. Below these lower planets by 30,000 yojanas, Śeṣa Nāga is lying on the Garbhodaka Ocean. That ocean is 249,800,000 yojanas deep. Thus the total diameter of the universe is approximately 500,000,000 yojanas, or 4,000,000,000 miles.
(Srimad Bhagavatam------5:23:9------purport).