By Swami Harshananda
Sometimes transliterated as: Sambhavimudra, ZAmbhavimudrA, shaambhavimudraa
śāmbhavimudrā (‘mudrā related to Śambhu [Śiva]’)
It is fixing the gaze on the light of the ātman, in the space between the eyebrows (vide Gheranda Samhitā 3.64-67), ultimately resulting in ātmajñāna. Such a yogi becomes like Ādinātha (Primeval Lord) or Nārāyaṇa.
According to another definition it is aiming at Brahman inwardly though the
gaze of the eyes is fixed outside, but seeing nothing. This technique learnt from a guru, through his grace, will lead to the realisation of the Śambhutattva or Śiva CHathayogapradīpikā 4.34-37).
The correct methods have to be learnt from a competent guru.
- The Concise Encyclopedia of Hinduism, Swami Harshananda, Ram Krishna Math, Bangalore