The following verses alone in all the upanishads describe to some degree the process of reincarnation.
Dreaming and waking
“Janaka said: ‘You shall have still another thousand cattle. Speak on, revered sir, for the sake of my liberation.’
“Yajnavalkya said: ‘The Self, having in dreams enjoyed the pleasures of sense, gone hither and thither, experienced good and evil, hastens back to the state of waking from which he started.’
“‘As a man passes from dream to wakefulness, so does he pass at death from this life to the next. When a man is about to die, the subtle body, mounted by the intelligent Self, groans–as a heavily laden cart groans under its burden.’
“‘When his body becomes thin through old age or disease, the dying man separates himself from his limbs, even as a mango or a fig or a banyan fruit separates itself from its stalk, and by the same way that he came he hastens to his new abode, and there assumes another body, in which to begin a new life.’” (Brihadaranyaka Upanishad 4:3:33-36).
Passing from life to life is only the shifting of a dream. When the stored-up life force (a form of karma) for a life is running out, just as the charge in a battery is expended and fails, so do the physical and grosser pranic bodies. And, just as the ripe fruit falls from the tree, so the subtle body separates itself from the material body and begins its process toward another earthly birth in a new body. In between births, the individual spends time in the astral regions, sometimes just wandering and frittering his time away, and sometimes in learning and evolving so his next life will be markedly better–and wiser–than the previous one. This time spent in this intermediate state can be anything from a matter of hours to centuries and even thousands of years. This is precisely determined by karma.
By the way, it is nonsense to say that unevolved people reincarnate quickly and evolved people only come back in thousands of years. Both ends of the spectrum are similar: very unevolved beings reincarnate very fast, and so do those that are highly evolved, for they are getting ready to graduate and are “cramming” for the final test.
Leaving the body
“‘When his body grows weak and he becomes apparently unconscious, the dying man gathers his senses about him and completely withdrawing their powers descends into his heart. No more does he see form or color without.
“‘He neither sees, nor smells, nor tastes. He does not speak, he does not hear. He does not think, he does not know. For all the organs, detaching themselves from his physical body, unite with his subtle body. Then the point of his heart, where the nerves join, is lighted by the light of the Self, and by that light he departs either through the eye, or through the gate of the skull, or through some other aperture of the body. When he thus departs, life departs; and when life departs, all the functions of the vital principle depart. The Self remains conscious, and, conscious, the dying man goes to his abode. The deeds of this life, and the impressions they leave behind, follow him.’” (Brihadaranyaka Upanishad 4:4:1,2).
He becomes apparently unconscious. This is important. The person may cease to perceive anything, but that is not being unconscious. We are never unconscious at any time, but we mistakenly call total absence of sensory perception unconsciousness. There is a vital point I want to mention here. The very last sense to fail is the sense of hearing. Sometimes it never fails. A lot of people give up and die because they hear the doctor say there is no hope or that they will soon be dead. So if you are around a dying, “unconscious” person please remember this. You can speak to them and help them either revive or go to higher worlds. That is why both Hindus and Buddhists read scriptures to the dying or recite or sing mantras. In Pure Land Buddhism people sit by the dying and sing the mantra of Amida Buddha, continuing to do so for several hours after the person appears to be dead, knowing that sometimes they may have trouble getting out of the body or may be disoriented when they do.
Yogananda spoke of this to his students, one of whom was the famous opera singer Amelita Galli-Curci. So when her brother was dying she talked to him and called him back to life. When he became fully conscious he told her that he had heard the doctor saying he would soon be dead, so he accepted it and began drifting away. Then he heard her voice calling to him from far off, and telling him to return. So he did. At one point he even saw Yogananda, about whom he knew virtually nothing but he recognized Yogananda when his sister showed a photograph to him.
It is sometimes possible to revive a person by intoning Om in their right ear. Yogananda also recommended this.
Then the point of his heart, where the nerves join, is lighted by the light of the Self, and by that light he departs either through the eye, or through the gate of the skull, or through some other aperture of the body. This is the Light that so many people tell about seeing who have returned from near-death. There are many gates by which a person may leave the body, and they are all determined by the level of consciousness (bhava) in which he has habitually lived during his lifetime. (This is one of the major teachings of the Bhagavad Gita.) To leave through a center in the head is the best, and will determine what highly evolved world he will enter. Those who leave through the center at the top of the head, the Brahmarandhra, will not return to rebirth. Those who leave at lower centers in the body or spine will go to lesser worlds, and some of the lowest centers are literally gates to the negative worlds we call “hells.” Some even lead to rebirth in animal forms, though this is rare.
The Self remains conscious, and, conscious, the dying man goes to his abode. The deeds of this life, and the impressions they leave behind, follow him. Some people of low evolution simply go to sleep and only wake a little before reincarnating, and some do not even awaken until they are born. But the people to which this upanishad is addressed will certainly depart in full consciousness and will review their life and be aware of the psychic changes their previous actions have produced. And they will be aware of exactly why and how they eventually find themselves in an astral or causal realm that corresponds to those karmas and samskaras. It is all a matter of learning.
Astral birth
“‘As a leech, having reached the end of a blade of grass, takes hold of another blade and draws itself to it, so the Self, having left this body behind it unconscious, takes hold of another body and draws himself to it.’” (Brihadaranyaka Upanishad 4:4:3).
Birth in the astral world is a conscious act. Only on earth or in the negative astral worlds do we mistakenly think that we are helpless and that we are not in charge. That is why the simile of a leech is used, and why the Sanskrit text literally says that we make another body for ourselves. And that happens in earthly rebirth, too. We choose where and to whom we will be born, and we enter the womb of our chosen mother and, taking the material provided by both parents, make our next body-habitation in accordance with our karma and samskara–this is how powerful and intelligent we all are. Yogananda says in his Gita commentary that the individual consciously guides the growth of his body in the womb. (That was the first sentence of Yogananda’s teaching that I read, sitting in a public library in the fall of 1960.).
“‘As a goldsmith, taking an old gold ornament, molds it into another, newer and more beautiful, so the Self, having given up the body and left it unconscious, takes on a newer and better form, either that of the fathers, or that of the celestial singers, or that of the gods, or that of other beings, heavenly or earthly.’” (Brihadaranyaka Upanishad 4:4:4).
In the higher worlds, the individual creates a body that is appropriate to the world in which he shall be living until he takes rebirth–also voluntarily. This experience will train him for even more efficiently making his body when he returns to earth.
Sometimes in the subtle worlds an individual takes on a body that is higher than his present evolutionary status and practices living on that level. This prepares him for a higher level on earth, as well. This is mentioned as taking place even for animals in the forty-third chapter of Yogananda’s autobiography, “The Resurrection of Sri Yutkeswar.”
Misidentification
“‘The Self is verily Brahman. Through ignorance it identifies itself with what is alien to it, and appears to consist of intellect, understanding, life, sight, hearing, earth, water, air, ether, fire, desire and the absence of desire, anger and the absence of anger, righteousness and the absence of righteousness. It appears to be all things–now one, now another.
“‘As a man acts, so does he become. A man of good deeds becomes good, a man of evil deeds becomes evil. A man becomes pure through pure deeds, impure through impure deeds.
“‘As a man’s desire is, so is his destiny. For as his desire is, so is his will; as his will is, so is his deed; and as his deed is, so is his reward, whether good or bad.’” (Brihadaranyaka Upanishad 4:4:5).
Lest in all this we forget that it is really the dream-life of the individual spirit, Yajnavalkya reminds Janaka of this. For in all these changes, the Self is unchanging, in all these births and deaths the Self remains birthless and deathless. The fact that we so easily forget this truth is evidence of how good we are at fooling ourselves. We are always masters of the situation.
Desire
“‘A man acts according to the desires to which he clings. After death he goes to the next world bearing in his mind the subtle impressions of his deeds; and after reaping there the harvest of his deeds, he returns again to this world of action. Thus he who has desires continues subject to rebirth.
“‘But he in whom desire is stilled suffers no rebirth. After death, having attained to the highest, desiring only the Self, he goes to no other world. Realizing Brahman, he becomes Brahman.’” (Brihadaranyaka Upanishad 4:4:6).
It is ignorance that causes our mistaken identification, but the power behind rebirth is desire. Once we cut off desire, rebirth is finished. Desireless, we transcend all worlds and know ourselves as Eternal Brahman.
“‘When all the desires which once entered into his heart have been driven out by divine knowledge, the mortal, attaining to Brahman, becomes immortal.
““As the slough of a snake lies cast off on an anthill, so lies the body of a man at death; while he, freed from the body, becomes one with the immortal spirit, Brahman, the Light Eternal.’
“Janaka said: ‘Sir, again I give You a thousand cows. Speak on, that I may be liberated.’” (Brihadaranyaka Upanishad 4:4:7).
All glory to those that have freed themselves by knowing their Self!
Read the next article in the Upanishads for Awakening: The Path of Liberation