In Bhagavad-gītā (14.14-15) it is said that those who are highly developed in the mode of goodness are promoted to the higher, heavenly planetary system, and those who are overpowered by the mode of passion are situated in the middle planetary systems—the earth and similar planets. But those who are surcharged with the mode of ignorance are degraded to the lower planetary systems or to the animal kingdom. The demigods are highly developed in the mode of goodness, and thus they are situated in the heavenly planets. Below human beings are the animals, although some of them mingle with human society; cows, horses, dogs, etc., are habituated to living under the protection of human beings.
(Srimad Bhagavatam------3:6:28------purport).

After the three worlds—the upper, lower and middle planetary systems—merged into the water of dissolution, the living entities of all the three worlds remained in their subtle bodies by dint of the energy called kāla. In this dissolution, the gross bodies became unmanifest, but the subtle bodies existed, just like the water of the material creation. Thus the material energy was not completely wound up, as is the case in the full dissolution of the material world.
(Srimad Bhagavatam------3:8:11------purport).

The cosmic manifestation is grossly divided into three worlds, the upper, lower and middle planetary systems, and then it broadens into the cosmos of fourteen planetary systems, with the manifestation of the Supreme Personality of Godhead as the supreme root. Material nature, which appears to be the cause of the cosmic manifestation, is only the agency or energy of the Lord. This is confirmed in Bhagavad-gītā (9.10): mayādhyakṣeṇa prakṛtiḥ sūyate sa-carācaram. "Only under the superintendence of the Supreme Lord does material nature appear to be the cause of all creation, maintenance and dissolution." The Lord expands Himself into three—Viṣṇu, Brahmā and Śiva—for maintenance, creation and destruction respectively. Of the three principal agents controlling the three modes of material nature, Viṣṇu is the Almighty; even though He is within material nature for the purpose of maintenance, He is not controlled by the laws of material nature. The other two, Brahmā and Śiva, although almost as greatly powerful as Viṣṇu, are within the control of the material energy of the Supreme Lord.
(Srimad Bhagavatam------3:9:16------purport).

The words haṁsena yānena are very significant here. Haṁsa-yāna, the airplane by which Brahmā travels all over outer space, resembles a swan. Brahmā is also known as Haṁsa because he can grasp the essence of everything. His abode is called tri-dhāma-paramam. There are three divisions of the universe—the upper planetary system, themiddle planetary system and the lower planetary system—but his abode is above even Siddhaloka, the upper planetary system. He returned to his own planet with the four Kumāras and Nārada because they were not going to be married. The other ṛṣis who came with him, such as Marīci and Atri, remained there because they were to be married to the daughters of Kardama, but his other sons—Sanat, Sanaka, Sanandana, Sanātana and Nārada—went back with him in his swan-shaped airplane. The four Kumāras and Nārada are naiṣṭhika-brahmacārīs. Naiṣṭhika-brahmacārī refers to one who never wastes his semen at any time. They were not to attend the marriage ceremony of their other brothers, Marīci and the other sages, and therefore they went back with their father, Haṁsa.
(Srimad Bhagavatam------3:24:20------purport).

Throughout the whole universe—in the higher, lower and middle planetary systems—Pṛthu Mahārāja's reputation was loudly declared, and all ladies and saintly persons heard his glories, which were as sweet as the glories of Lord Rāmacandra.
In this verse the words strīṇām and rāmaḥ are significant. It is the practice amongst ladies to hear and enjoy the praises of certain heroes. From this verse it appears that Pṛthu Mahārāja's reputation was so great that ladies all over the universe would hear of it with great pleasure. At the same time, his glories were heard all over the universe by the devotees, and they were as pleasing as Lord Rāmacandra's glories. Lord Rāmacandra's kingdom is still existing, and recently there was a political party in India named the Rāmarājya party, which wanted to establish a kingdom resembling the kingdom of Rāma. Unfortunately, modern politicians want the kingdom of Rāma without Rāma Himself.
(Srimad Bhagavatam------3:22:63------translation and purport).

Śrīla Rūpa Gosvāmī has said that the position of a devotee is so superexcellent that a devotee does not consider any material opulence worth having. There are different types of opulences on earth, in the heavenly planets and even in the lower planetary system, known as Pātāla. A devotee, however, knows that they are all material, and consequently he is not at all interested in them. As stated in Bhagavad-gītā, paraṁ dṛṣṭvā nivartate (B.G.5:19). Sometimes yogīs and jñānīs voluntarily give up all material opulences to practice their system of liberation and taste spiritual bliss. However, they frequently fall down because artificial renunciation of material opulences cannot endure. One must have a superior taste in spiritual life; then he can give up material opulence. Mahārāja Priyavrata had already tasted spiritual bliss, and therefore he had no interest in any of the material achievements available in the lower, higher or middle planetary systems.
(Srimad Bhagavatam------5:1:41------purport).

Those who act in the mode of goodness are promoted to higher planetary systems to become demigods, those who act in an ordinary way and do not commit excessively sinful acts remain within this middle planetary system, and those who perform abominable sinful actions must go down to hellish life.
(Srimad Bhagavatam------6:1:45------purport).

Persons who fully surrender at the lotus feet of the Supreme Personality of Godhead and always think of His lotus feet are accepted and recognized by the Lord as His own personal assistants or servants. The Lord never bestows upon such servants the brilliant opulences of the upper, lower and middle planetary systems of this material world. When one possesses material opulence in any of these three divisions of the universe, his possessions naturally increase his enmity, anxiety, mental agitation, pride and belligerence. Thus one goes through much endeavor to increase and maintain his possessions, and he suffers great unhappiness when he loses them.
(Srimad Bhagavatam------6:11:22------translation).

O unlimited one, if Your Lordship is satisfied, one can very easily obtain a lifetime as long as that of Lord Brahmā, a body either in the upper, lower or middle planetary systems, unlimited material opulence, religion, economic development and satisfaction of the senses, full transcendental knowledge, and the eight yogic perfections, what to speak of such petty achievements as conquering one's rivals.
(Srimad Bhagavatam------8:7:10------translation).

Lord Vāmanadeva indirectly indicated to Bali Mahārāja that he was occupying more land than he needed. In the material world, all distresses are due to extravagance. One acquires money extravagantly and also spends it extravagantly. Such activities are sinful. All property belongs to the Supreme Personality of Godhead, and all living beings, who are sons of the Supreme Lord, have the right to use the Supreme Father's property, but one cannot take more than necessary. This principle should especially be followed by brāhmaṇas and sannyāsīs who live at the cost of others. Thus Vāmanadeva was an ideal beggar, for He asked only three paces of land. Of course, there is a difference between His footsteps and those of an ordinary human being. The Supreme Personality of Godhead, by His inconceivable prowess, can occupy the entire universe, including the upper, lower and middle planetary systems, by the unlimited measurement of His footsteps.
(Srimad Bhagavatam------8:19:17------purport).