Spanda is a Sanskrit term – derived from the root spadi: "to move a little" (kimcitcalana) – for the subtle creative pulse of the universe as it manifests into the dynamism of living form.
The Spanda system is usually described as "vibration/movement of consciousness". Abhinavagupta uses the expression "some sort of movement" to imply the distinction from physical movement; it is rather a vibration or sound inside the Divine, a throb. The essence of this vibration is the ecstatic self-recurrent consciousness.
The central tenet of this system is "everything is Spanda", both the objective exterior reality and the subjective world. Nothing exists without movement, yet the ultimate movement takes place not in space or time, but inside the Supreme Consciousness (cit).
So, it is a cycle of internalization and externalization of consciousness itself, relating to the most elevated plane in creation (Śiva-ŚaktiTattva).
A statue of Shiva as Nataraja, 'lord of the dance', at an Indian temple. The dance is symbolic of universal creation and destruction.
Vasugupta (c. 800 CE) wrote the Śiva SutrasSpandaKarika and VijñānaBhairava Tantra the most important texts of the Spanda system.,
The Shiva Sutras, a collection of aphorisms which belong to the agamas, expound a purely non-dual (Advaita) metaphysics. Traditionally, the Shiva Sutras are considered to have been revealed to Vasugupta by Shiva.
The knower of the mystery of sound knows the mystery of the whole universe.
- Hazrat Inayat Khan, Sufi Teacher