Vijnana Bhairava Tantra · Dharana 69 · Verse 92
Yourself as open space
Sit and look at the empty volume of the room: not the furniture, but the space the furniture sits in. Let attention rest as that volume. Then let the walls fall away in the mind, and feel yourself as space without a boundary in any direction. The objects can stay where they are. You are practicing space, not interior design.
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Meditate on your own self as space, unbounded in every direction. Then the power of awareness, needing no support, reveals your true nature.