The vision of the devotees is not ordinary; it is purified by the process of devotional service. In other words, as the universal elements are both within and without, similarly the Lord's name, form, quality, pastimes, entourage, etc., as they are described in the revealed scriptures or as performed in the Vaikuṇṭhalokas, far, far beyond the material cosmic manifestation, are factually being televised in the heart of the devotee. The man with a poor fund of knowledge cannot understand, although by material science one can see things far away by means of television. Factually, the spiritually developed person is able to have the television of the kingdom of God always reflected within his heart. That is the mystery of knowledge of the Personality of Godhead.
(Srimad Bhagavatam-----2:9:35-----purport).

As stated in the Brahma-saṁhitā (5.35):
eko 'py asau racayituṁ jagad-aṇḍa-koṭiṁ
yac-chaktir asti jagad-aṇḍa-cayā yad-antaḥ
aṇḍāntara-stha-paramāṇu-cayāntara-sthaṁ
govindam ādi-puruṣaṁ tam ahaṁ bhajāmi
"I worship the Personality of Godhead, Govinda, who, by one of His plenary portions, enters the existence of every universe and every atomic particle and thus unlimitedly manifests His infinite energy all over the material creation." To create this cosmic manifestation, Govinda, the Supreme Personality of Godhead, expands His external energy and thus enters everything in the universe, including the atomic particles. In this way He exists in the entire cosmic manifestation. Therefore the activities of the Supreme Personality of Godhead in maintaining His devotees are transcendental, not material. He exists in everything as the cause and effect, yet He is separate, existing beyond this cosmic manifestation.
(Srimad Bhagavatam-----7:9:30-----purport).

The Supreme Personality of Godhead is situated in pure goodness (śuddha-sattva), and therefore He is eka-varṇa—the oṁkāra (praṇava). Because the Lord is beyond the cosmic manifestation, which is considered to be darkness, He is not visible to material eyes. Nonetheless, He is not separated from us by time or space, but is present everywhere. Seated on His carrier, Garuḍa, He is worshiped by means of mystical yogic power by those who have achieved freedom from agitation. Let us all offer our respectful obeisances unto Him.
(Srimad Bhagavatam-----8:5:29-----translation).

When many seeds are placed in an agricultural field, innumerable manifestations of trees, bushes, vegetables and so on will arise from a single source, the soil. Similarly, the Supreme Personality of Godhead, who gives life to all and is eternal, originally exists beyond the scope of the cosmic manifestation. In the course of time, however, the Lord, who is the resting place of the three modes of nature and the source of the universal lotus flower, in which the cosmic manifestation takes place, divides His material potencies and thus appears to be manifest in innumerable forms, although He is one.
(Srimad Bhagavatam-----11:12:20-----translation).

The Vedas inform us that beyond this cosmic manifestation there are extensive planets and the spiritual sky. This material manifestation is regarded as only a small portion of the total creation. The material manifestation includes not only this universe but innumerable others as well, but all the material universes combined comprise only one fraction of the total creation. The majority of the creation is situated in the spiritual sky. In that sky innumerable planets float, and these are called Vaikuṇṭhalokas. In every Vaikuṇṭhaloka Nārāyaṇa presides in the form of His four-armed expansions: Saṅkarṣaṇa, Pradyumna, Aniruddha and Vāsudeva.
(Teachings of Lord Caitanya).

This cosmic manifestation is called "nature," but there is another nature, which is superior. The cosmic manifestation is inferior nature, but beyond this nature, which is manifested and unmanifested, there is another nature, which is called sanātana, eternal. It is easy to understand that everything manifested here is temporary. The obvious example is our body. If one is thirty years old, thirty years ago his body was not manifested, and in another fifty years it will again be unmanifested. That is a factual law of nature. It is manifested and again annihilated, just as waves in the sea rise frequently and then recede. The materialist, however, is simply concerned with this mortal life, which can be finished at any moment. Furthermore, as this body will die, so the entire universe, this gigantic material body, will be annihilated, and whether we are fortunate or unfortunate, on this planet or another planet, everything will be finished. Why then are we wasting our time trying to go to a planet where everything will be finished? We should try to go to Kṛṣṇaloka. This is spiritual science; we must try to understand it, and, after understanding it ourselves, we should preach this message to the whole world. Everyone is in darkness. Although people have no knowledge, they are very proud. But it is not advancement of knowledge to go to the moon after ten years of effort and take a rock and come back. The space travelers are very proud: "Oh, I have touched it." But what have they gained? Even if we were able to live there, it would not be for long. It will all be destroyed in the end.
(Easy Journey to other Planets).

Kṛṣṇa took compassion upon Brahmā because of his inability to see how Kṛṣṇa was displaying the forms of Viṣṇu and transforming Himself into calves and cowherd boys, and thus, while fully manifesting the Viṣṇu expansions, He suddenly pulled His curtain of yogamāyā over the scene. In the Bhagavad-gītā it is said that the Supreme Personality of Godhead is not visible due to the curtain spread by yogamāyā. That which covers the reality is mahā-māyā, or the external energy, which does not allow a conditioned soul to understand the Supreme Personality of Godhead beyond the cosmic manifestation. But the energy which partially manifests the Supreme Personality of Godhead and partially does not allow one to see is called yogamāyā. Brahmā is not an ordinary conditioned soul. He is far, far superior to all the other demigods, and yet he could not comprehend the display of the Supreme Personality of Godhead; therefore Kṛṣṇa willingly stopped manifesting any further potency. The conditioned soul not only becomes bewildered but is completely unable to understand. The curtain of yogamāyā was drawn so that Brahmā would not become more and more perplexed.
(Krsna Book).

There is a spiritual sky. There is another nature, which is beyond manifestation and nonmanifestation. But how will you know that there is a sky where the planets and inhabitants are eternal? All this knowledge is there, but how will you make experiments? It is not possible. Therefore you have to take the assistance of the Vedas. This is called Vedic knowledge. In our Kṛṣṇa consciousness movement we are accepting knowledge from the highest authority, Kṛṣṇa. Kṛṣṇa is accepted as the highest authority by all classes of men. I am speaking first of the two classes of transcendentalists. One class of transcendentalists is called impersonalistic, Māyāvādī. They are generally known as Vedāntists, led by Śaṅkarācārya. And there is another class of transcendentalists, called Vaiṣṇavas, like Rāmānujācārya, Madhvācārya, Viṣṇu Svāmī. Both the Śaṅkara-sampradāya and the Vaiṣṇava-sampradāya have accepted Kṛṣṇa as the Supreme Personality of Godhead. Śaṅkarācārya is supposed to be an impersonalist who preached impersonalism, impersonal Brahman, but it is a fact that he is a covered personalist. In his commentary on the Bhagavad-gītā he wrote, "Nārāyaṇa, the Supreme Personality of Godhead, is beyond this cosmic manifestation." And then again he confirmed, "That Supreme Personality of Godhead, Nārāyaṇa, is Kṛṣṇa. He has come as the son of Devakī and Vasudeva." He particularly mentioned the names of His father and mother. So Kṛṣṇa is accepted as the Supreme Personality of Godhead by all transcendentalists. There is no doubt about it.
(Sri Isopanishad).