Vignana Bhairava Tantra - 81

Ha...ha....ha....

Madhya Jihve Spharitasye Madhye Nikshipya Chetanam|

Hoccharam Manasa Kurvaha Tatah Shante Praleeyate||

Placing the tip of the tongue on the upper palate, in the mouth opens up the passage of energychannels that run through the Agnya Chakra (between the eyebrows) and the Sahasrara (Crown centre of the head). Staying in this mudra, which is similar to the Kechari and chanting 'Ha' with the exhalation that follows a deep inhalation, the mind attains to peace.

- Swahilya Shambhavi

Vignana Bhairava Tantra - 77

Realisation through Mudras

Karankinya Krodhanaya Bhairavya Lelihanaya|

Kecharya Drishtikalecha Paraavaptih Prakashate||

Five Mudras of the Tantric practice are mentioned here. Mudras are postures of the body and mind. They are to be practised only under the guidance of a Guru. Seated in a mudra and focussing one's attention on it, the Supreme truth is revealed. - Swahilya Shambhavi.