Śivasaṃhitā 2.11

This verse exposes a fundamental paradox in yogic subtle physiology: the inner Sun is both the engine of life and its principal consumer. It devours pīyūṣa, the lunar nectar secreted from the cranial center, as well as the essential substances of the bodily tissues. Solar fire animates the organism, but left unchecked it exhausts the very reserves that sustain consciousness and longevity.

Pīyūṣa (ambrosia, nectar) and dhātu (bodily tissue, substance) are the two targets of solar consumption. The seven dhātus of Āyurvedic medicine — from plasma to reproductive essence — represent the body’s most refined material resources. The verb grasati (to swallow, to devour) frames the Sun as an active predator within the body, making aging itself a form of internal combustion.

This teaching directly motivates practices like viparīta karaṇī, the inverted posture designed to prevent the lunar nectar from dripping into the solar fire below. By reversing the body’s orientation, the downward flow of amṛta from the bindu center is interrupted. The verse thus belongs to a coherent physiological argument that runs through many Hatha Yoga texts, justifying an entire repertoire of conservatory practices.