There are many forms of yoga. Some forms of yoga deal with controlling the bodily functions. In our body we have two currents. We have the motor currents and the sensory currents flowing through our bodies. The motor currents keep us alive, by controlling our involuntarily body functions, such as the growth of our nails and hair, our breathing, and our blood circulation.
In meditation on the inner Light and Sound, one does not practice the control of the motor currents for transcending the body. The motor currents are allowed to go on by themselves so that the process by which we survive in this world is not tampered with. Instead, we withdraw the sensory currents. The sensory currents give us sensation in the body. It is the sensory currents which make us aware of the sense of sight, hearing, smell, taste, and touch. If we withdraw our sensory currents from the outside world, and collect them at the eye-focus, we will be able to travel to the realms within.
Meditation is, in reality, a process of concentration. It is so simple and natural that it can be practiced by a young child or the elderly, by a healthy person or someone with a physical disability. Meditation does not require any asanas or difficult postures or any rigorous physical activity. It is a nondenominational technique that has been practiced by people of all religions and faiths, cultures, and backgrounds, as a science. It is open to one and all, and has been offered as a free gift by the spiritual Masters who have come throughout the ages. It is up to us whether we wish to merely read about the realms beyond, or experience them. The saints tell us that being made of matter, the physical body deteriorates, decays, and is finally destroyed. But our true self, which is our spirit or soul, is eternal. It lives on and on. By connecting with our soul, we will have access to the answers of what awaits us beyond.