Śivasaṃhitā 4.27

This verse describes the beginning of the physical posture of Mahāmudrā: the left heel (apasavyena pādamūlena) presses with reverence (sādaram) a specific area of the perineum or root of the thigh. The word sampīḍya (‘having compressed’, ‘pressing’) indicates a deliberate and sustained action, not mere contact. The left foot serves as an instrument for stimulating mūlādhāra.

Apasavya literally means ‘contrary to the auspicious side’, i.e., the left side. In Vedic ritual, savya is the right side, the side of the chief priest; apasavya designates the opposite. Pādamūla (‘root of the foot’, ‘heel’) is the instrument of pressure. Sādaram (‘with respect’, ‘with care’) underscores the contemplative attitude that must accompany the physical gesture.

The technique of pressing the perineum with the heel is shared by several Hatha Yoga mudrās, including siddhāsana and mūlabandha. This physical pressure on the perineal region stimulates mūlādhāracakra and facilitates the awakening of kuṇḍalinī. The instruction to begin with the left side reflects the energetic logic of the nāḍī system, where iḍā (the lunar, left channel) precedes piṅgalā.