We say there are four bodies in a human being; the physical, the subtle, the causal and the supra-causal. Our intellect, for the purpose of understanding, likes to break the one into many, likes to separate the whole into different parts. To be clear, there is only one consciousness appearing in four different states. This one consciousness is not linked to four separate things, four separate bodies. It is the same consciousness that experiences, functions and illumines through the senses, that sees our dreams, experiences deep sleep and is the pure Self in the transcendent state. In reality, there aren’t four separate bodies. I’ll repeat this; there is one consciousness appearing in four different states. It is like one lotus with four petals.
The physical body:
In its physical, gross appearance, consciousness experiences the pairs of opposites; pain and pleasure, happiness and sadness, good and evil. It is equipped with the senses, the organs of action, the different pranas and is linked to the psychic instruments (mind). This body allows us to physically act. This appearance of consciousness experiences the waking state. In meditation we see this body as red light and its seat of power is in the eyes. It is the size of our physical body.
The subtle body:
In its subtle or astral appearance, consciousness experiences dreams. It creates imaginary worlds, circumstances and events mainly as the result of purification and rejuvenation brought on by deep rest, and it receives information and help form the great beings. In meditation we see this body as white light and its seat of power is in the throat. As the subtle body, consciousness performs the three distinct functions of mind; thinking, ego and intellect. The subtle body holds samskaras, old impressions, that are currently activated. It is the size of the thumb.
The causal body:
In its causal appearance, consciousness experiences deep, dreamless sleep, beyond the senses and beyond desires. In this appearance, when illumined, bliss is enjoyed. In meditation we see this body as the black light of the velvety void and its seat of power is in the heart. It is beyond thoughts and feelings. This body holds all the inactive impressions of our countless lifetimes, all of our samskaras. It is called causal because it is these samskaras that hold the karma that determines, that causes, the creation of our subtle and physical bodies. It is the vehicle that allows us to travel to other subtle worlds. It is the size of the index finger tip.
The supra-causal body:
From an intellectual standpoint we call this the fourth body, but in actuality it is not a body. It is turiya, the transcendental state. So, if we think of it as a body, it is one of pure consciousness. This is the pure Self, the ultimate reality. This appears as the neela bindu, the seed of infinite power. It is Shiva, the Atman, pure consciousness, unmanifest, unmoving, immortal awareness. This is the witness. In meditation we see this body as the blue pearl, God, and its seat of power is in the sahasrar. It is the size of a small pearl or lentil seed.
At the time of death, it is only the physical body that falls away. The subtle, causal and supra-causal bodies transmigrate to take on another body in the process of reincarnation.