There is an outer form of sacrifice in the Vedic tradition, which was heavily practiced and continues today in Hindu society. These forms are highly regulated in order to achieve optimal results, which are traditionally connected to various forms of success or benefits in the external world of life and action. These outer forms correspond to similar traditions around the world, such as praying to certain Saints in the Christian tradition to obtain specific results. Yet there is also an inner significance to the Vedic sacrifice as Sri Aurobindo has described, and this inner sense is more consistent in terms of the action and the result than the external sense which confused so many Western scholars when they attempted to understand the Vedas and the Upanishads, and came away with the idea that the profoundest ideas were mixed up with confused seeking after worldly results.
Mundaka Upanishad, Chapter 1, Section 2, Verse 3 continues the description of the Vedic sacrifice and its proper form. Sri Aurobindo translates: “For he whose altar-fires are empty of the new-moon offering and the full-moon offering and the offering of the rains and the offering of the first fruits, or unfed, or fed without right ritual, or without guests or without the dues to the Vishwa-Devas, destroys his hope of all the seven worlds.”
The seven worlds correspond to the 7 layers or dimensions of existence, the physical, the vital, the mental, the knowledge-consciousness, and the 3 higher realms, Sat-Chit-Ananda, existence-consciousness-bliss. These in turn relate to the 7 primary chakras that act as energy centers within the human individual and channel the powers of the 7 realms into their human action. We may not, today, be able to ascertain the specific psycho-spiritual aspects corresponding to the “new moon” or “full moon” or other offerings, but it is certainly indicative of the all-embracing nature of the fire of aspiration expected of the seeker in his attempt to obtain the spiritual realisation. The Vishwa-Devas are the powers of existence that correspond to the physical and material world, the vital world, the mental world, etc. These powers must be recognized, supported and developed in order to bring about the full development of the world. All of this, however, falls under the rubric of the “lower knowledge” of the manifested universe rather than the “higher knowledge” of the Immutable.
Sri Aurobindo, The Upanishads, Mundaka Upanishad, pp. 193-210