It is important in the practice of yoga asana to not simply repeat the same mis-takes on reality we make during our normal waking hours. One of this mis-takes is the illusion that form and substance are primary, whilst space and emptiness are secondary or even ignored. How often during your day-to-day living do you give attention to the space around you, the space within you, the between you and other people, the space between each of your thoughts and between each breath?
According to mystics, yogis, and modern science, most of the universe is empty space. This observation does not simply apply to that vast and readily apparent stretches of empty space out in “space” (galaxies, etc.). This observation applies just as much to the space within your own body. The human body is almost entirely space, with the minutest amount of matter or physical substance. The atoms which make up your body are almost entirely empty space.
An important, simple, and powerful secret I share with aspiring Yogis is that of giving their attention to the space (within and around their body) rather than focusing solely on the form of their body. Because the majority of people give all attention to form out of habit it can take some practice before our experience of space becomes more tangible, more alive, and more persistent.
When we do yoga with all of our attention on the form of the body is it really yoga? Yoga is union of the many into the One. At an individual level yoga is union of the many dimensions of Man. Body, mind, spirit, Life, breath, prana, the Supreme Source, etc.. But if the physical aspect of the body is only a fraction of a percent of what actually constitutes Man, union is impossible if that is all the yoga practitioner gives his or her attention to.
In Hṛdaya Yoga attention is given to the form aspect of the body only as much as is necessary to draw ones awareness into the formless aspect of the body. We utilise the form as a doorway or entry point into the formless. This is not actually that difficult to do, it only requires a fairly simple shift in ones approach to yoga asana, to the breath, and to the overall experience.