Agni is the key principle of Vedic knowledge and the basis of Yoga and Ayurveda. At a cosmic level Agni is ultimately Chid-Agni or the fire of Universal Consciousness and Tapoloka, the sixth of the seven lokas where pure light prevails.
In Ayurveda and Yoga we recognize the Jatharagni or digestive fire as the basis of the physical body and health, the Pranagni or Pranic fire as the basis of our vital energy system, the eye as the Agni or fire among the senses, the Buddhi or discriminating intelligence as the fire of the mind, and Premagni, the fire of Divine love as the basis of bliss and happiness (Ananda).
The individual reincarnating soul or Jivatman is also Agni as our indwelling core fire and immortal flame. The universal Self or Paramatman is the infinite Agni often symbolized by the Sun.
Vedic Agni Yoga consists of mantra, meditation and Self-inquiry, searching out and offering ourselves to the highest flame of truth within us (Brahmagni).