In this 56th verse and dharana of Vigyana Bhairava Tantra, Shiva says:
Sitting right, arms forming a circle
Attention within this circle of void
Relax mind into Shiva
Understanding the concept of void is more important than the posture.
Sit tight, with spine erect, lower back, neck and head in alignment, breathing easily and comfortably, sitting relaxed on a firm but comfortable seat. Extend arms forming a circle and focus attention within and inwards. Move into the mindless, bodyless, energy full state of Shiva.
Buddha termed this state sunya or void. Some of his disciples interpret this as his denying god, since he prescribed this state for nirvana or enlightenment. This is an unfortunate interpretation. The sunya as a circle is a representation of continuity and infinity as well. It is a continuum of the mind reaching out beyond the body boundaries and thought emotion boundaries into that state of its own creation, that of energy. When we transcend the mind body space we move into energy, which seems as the void, as there is no mind to grasp this state.
Buddha’s meditation vipassana is a process designed to create this energy space of void. Through breath awareness and body awareness one gradually transcend the mind body state of energy, void. Many, including me, have experienced this state in vipassana.
Yoga Nidra when practiced right leads to this state of void, which the Mandukya Upanishad calls Turiya. This process is described in my articles on Mindlessness in www. coacharya.com. Several verses later Shiva also talks about mindlessness. Buddha’s sunya or void is the same as Shankara’s purna or fulfillment.
What the Isa Vasya Upanishad shanti mantra states as:
That is complete, this is complete
From completeness arises completeness
When completeness comes out of completeness
The word purna can be translated as full, complete, infinite etc. This verse, the first verse of all Upanishads says that we and the universe are energy. The universe is an energy hologram and we are a chip of it, truly reflecting it completely. Once we understand, realize and experience this existential reality we can only move up.