To understand their nature it might be helpful to envision the physical body with two other bodies encompassing it. These other bodies are not physical, rather, they are non-physical.
They are ephemeral bodies – highly ordered spiritual extensions of the human body. They are called the astral body and the causal body. Without them, the physical body could not survive . They are embedded in each other. The ephemeral bodies exist and create in a dimensional realm just adjacent to our three dimensional reality.
It is wondrous to imagine what ancient yoga seers first discovered with the aid of meditation as they pierced through the dimensional veils to examine the astral body. They report to have seen energy circulate through the astral body’s system in a pattern that corresponds to the physical body’s circulatory system, which moved along prescribed paths creating energy vortexes. When this energy moved up into the area of the astral body which corresponded to the spine, the energy passed into definite centres of swirling energy. Within these centres, stellar energies were observed which moved in a cascade of light and sound. There were six centres along the spine and a seventh at the crown of the head. As energy passes through these centres, it is charged and refocused. They called these centres Chakras.
Funnels of light energy, rainbows of colour, circulate through the astral body. The force which was circulating was the underlying animating energy of life itself. They called this energy, Prana. Prana is the elemental catalytic energy that is within all living things. Prana is within all three bodies. Prana is in all physical things but is not physically manifest. The circulation of Pranic energy through the astral body is done through channels or tubes that are called Nadis. Each chakra contains a certain number of Nadis and these possess tone or vibration. These centers activate and circulate energy. Each Chakra center is uniquely designed to transport energy through the focus of its particular prism and create the physical body. The physical body, is also made up of sound and light, appearing in this three-dimensional reality as skin, blood and bones. Like the astral body, the physical body circulates energy through a system of nerves and ganglia.
The six Chakras correspond to the nerve plexus along the spine.
At the base of the spine is Muladhara, which corresponds to the sacral plexus.
Next is Swadhisthana corresponding to the prostatic plexus.
Manipura, the third chakra, corresponds to the solar plexus.
Anahata, the fourth chakra, is located in the heart region and corresponds to the cardiac plexus.
Vishuddha, the fifth chakra, is in the throat region and corresponds to the laryngeal plexus.
Ajna, the sixth chakra is located between the eyebrows and corresponds to the cavernous plexus.
Sahasrara the seventh chakra is located at the crown of the head and corresponds to the pineal gland.
The transference of pranic energy from the astral body to the three-dimensional physical body is achieved through various means. Prana or vital life energy is primarily absorbed by the breathing of air. It is also in the food we eat and the water we drink. Our mind can also produce pranic energy with the use of the imaginative process, focused on emotions and intelligence.
Meditation on the chakras is a powerful means of increasing pranic energy. Meditation on the individual chakra charges the body with energy. You will be flooded with extra pranic energy as you meditate on the succession of Chakras along your spinal column.
Chakra meditations are both mentally and physically felt. In deep forms of Chakra meditation the serpent energy which lies coiled at the base chakra, Muladhara is awakened and ascends through the upper chakras. As this energy enters into the chakra centres, it is altered through the chakras’ own velocities and patterns. Once you come to the seventh chakra, the intensity is palpable. The seventh chakra contains one thousand nadis and is a flurry of energy; a crescendo of light and sound. The environment within this last chakra is the most energetic. The components of the seventh chakra can launch normal consciousness into other dimensions of reality – out to levels of existence beyond time, space, and causation. This stage is very difficult and remote and there are worlds of psychic experience necessary before this last stage will ever be experienced or understood.
Most importantly, you must direct your attention and love towards your own being. In effect, you must flip your mind inside out – turn it back onto itself. Because the phenomenon of the chakras is both manifestly real and spiritually real, their various realities can be realised with the use of specific chakra meditations. But before actual progress in these meditations can occur, a certain quality of innocent discovery must first be cultivated in the psyche of the meditator. You must approach your inner reality with as much credulity as you do your outer reality. You can not succeed without this fundamental attitude.