Shoonya means 'nothingness'. There are two experiences in Yoga. One is of shoonya and the other is of jyoti, light. In the state of shoonya, the activity of consciousness, mind and ego stops, and there is only the awareness of consciousness and prana. The state of shoonya also known as nirvana, freedom from the bondage of life and mind. This freedom is the purpose of Buddhist meditation - teaching the state of nirvana where the activity of mind, intellect and emotions comes to a total standstill.
In Yoga, we use shoonya meditation as a step from dharana to dhyana. It is considered to be one of the important practices for people who want to reach higher meditative states, because it aims to bring about a state of no activity within the framework of body and mind. Later on, it can give rise to the awareness of higher consciousness. The dissociation between body and mind, mind and spirit is necessary in order to establish ourselves in the state of higher consciousness, There are various concepts concerning shoonya meditation, but in brief, it is, a series of practices which go deeper and deeper into the different layers of our experience and of the mind. In the first basic practice, the body is visualised in the form of an empty shell. The concentration is placed in hridayakasha, the heart space, and there ate concepts, of different spaces or heavens, within the bodily frame. In Yoga, we know of chidakasha which is contained in the head area. Then there is the concept of hridayakasha, the space contained in the region of the heart, and of daharakasha.
The purpose of taking the awareness to hridayakasha is to internalise the experiences of chitta, the mind. Concentration in chidakasha is required when we are practising techniques of pratyahara and dharana, and when we are learning how to handle the mental activity, the senses, the perceptions of the senses and intellect, the karmendriyas and gyanendriyas. However, when we try to go beyond the experiences of the karmendriya and gyanendriya, and try to have the feeling of nothingness, shoonya, then the concentration is taken down to hridayakasha. Hridayakasha is also the symbolic seat of the golden egg, hiranyagarbha, which is considered to be the state of solar consciousness. By experiencing the body as an empty shell, hollow inside, there is an automatic disassociation between mind and body. So, the experience of mind is totally cut off. As long as we are aware of the body, aware of various sensations, feelings and emotions related with the body, emotions and mind arise. There has to come a time in our spiritual sadhana when we bypass the experiences of chitta, mind, buddhi, intellect, manas, mental patterns and experiences and ahamkara, self-identity or ego.
The practices of shoonya meditation are directed towards achieving the experiences which come beyond the states of chitta, buddhi, manas and ahamkara. These are progressive meditative states, but after we have transcended the experience of these four faculties, then what we experience is just nothingness - total disassociation. This is because the highest, most positive experience in Yoga is the experience of union, but we also have the other aspect of Yoga, which is dissociation before the experience of association.
Initially, in the practices of pratyahara, which are the basic techniques for learning how to deal with the mind, what steps do we take? First we gather all the faculties together, and after they are withdrawn we project them outwards again. So, there is always the stage of coming hack first, and then reaching forward from this point.
After the state of shoonya has been reached, this meditation gradually evolves into the meditation in order to derive an understanding of the working of and the relationships between the body, mind and spirit, the concept of the trinity - matter, energy and the consciousness. This is the next area of sadhana which follows the practices of asana and pranayama, pratyahara and dharana and we should direct our efforts towards achieving the state of shoonya, and from there the state of jyoti.
Paramahamsaji has said that after the practice of asana, pranayama, pratyahara and dharana, before reaching into the meditative state of dhyana, you simply go through a process of experiencing the mind in its various phases. For this reason the shoonya experience should be evolved.
Shoonya meditation involves many different visualisations and about twelve different practices, which slowly take the mind deeper and deeper into the state of void. In the twelfth meditation one can achieve nirvana, but that becomes very intense.
Shoonya meditation can he combined with other types of meditation. For example, you can do mantra meditation, antar mouna (thought observation), chidakasha dharana (concentration in chidakasha), and at the end of those practices you can simply go into shoonya state - that is acceptable.
There are many yogas, like Laya Yoga, Nada Yoga, and many others which are not even known about in Western society, and each Yoga and the practices involved can induce a different state of shoonya, but it is a different meditative state of Yoga and the practices have not been taught in the West.
Sit in any comfortable meditation pose - check that your head and spine are erect and steady but not tense - become aware of the whole physical body from the top of the head to the tip of the toes - mentally go through the body and begin to relax it systematically - keeping the body still, discover any points of tension and relax those - if there is any pain or discomfort anywhere then accept it - be as comfortable and as still as you can - (pause).
Develop an image of the whole body at one homogeneous unit - one steady image - intensify your mental awareness of the whole physical body - imagine that before you there is a full length mirror - look into the clear surface of the mirror and see the reflection of your body in this mirror - maintain complete awareness of the whole reflected body - try to have a clear vision without too much effort - just as someone else would be able to see you from outside, see yourself reflected in the mirror of your mind - (pause).
Begin to develop the feeling of complete silliness within the physical body - focus your attention only on this inner stillness - inside you are calm and serene - along with the experience of motionlessness and calm you are to create the experience of inner silence - your entire bring is pervaded by and infused with the strength of stillness and the depth of silence - absolute motionlessness; deep and abiding silence - (pause).
Now imagine that your body is hollow from inside - there is only the external shell of skin - inside the entire body there is nothing but space - this external shell maintains the identity of the individual personality, but apart from this the body is totally empty - (pause).
When you submerge an empty glass in a body of water, what happens? The water is all around the glass and it is also contained within the glass, but there is a partition formed by the glass itself - this partition appeals to separate the water into two different substances or flows - in the same way, try to experience that you are floating in an ocean of energy and consciousness in which your body and mind exists.
The very same energy and consciousness which surrounds the body and the environment around us contains the causal body a so - this is the experience of the body as being nothing but an empty shell - there it no one except you, floating at total case in an ocean of energy, space and consciousness - try to develop the feeling of profound silence, stillness and calm penetrating everywhere, both within and without as you float at perfect ease - the experience of the body is like a big empty cave - experience the stability of the body and mind - experience infinite silence within body and mind - expand and intensify this feeling, this awareness - (pause).
Now, take your awareness to hridayakasha - the space in the centre of the body, near the heart - the space inside the physical cave - steady the attention, the awareness and one-pointedness at hridayakasha and begin chanting 'OM' - feel the vibration of 'OM' penetrating your being - the mantra 'OM' is vibrating inside the body and mind - (pause) begin to move the awareness from chakra to chakra within the body - continue, this practice for a minimum of ten minutes.
Now, stop this practice and remain quiet for a few minutes as you feel the space and silence inside yourself, and around you in the environment - (pause). The practice is now over - very slowly and gradually externalise your consciousness and gently begin to move your body keeping the eyes closed - finally, when you are feeling externalised, open your eyes. Om Tat Sat.