Since 1800 BCE, Hinduism has developed and changed.  The evolution of Hinduism progressed through its very distinct eras, beginning with the early Vedic era followed by the renunciation or Yoga era and their eventual synthesis with the Laws of Manu, and finally the more modern Bhakti and Tantric eras.  Through the development of Hinduism the unifying theme of sacrifice evolved reflecting the respective eras very distinct religious goals.

     The Vedic era, lasting between 1800 and 1200 BCE was community based and built on a world-loving cosmology.  Beginning with the Aryan invasion, sacrifice became very ritualized.  Yajna, the ritual act of sacrifice, was usually done through Agni, or fire.  Fire, they reasoned, provided the mouth by which the gods eat the sacrifices made to them via the smoke that emanated from the fire (The Hindu Tradition, 20).  What they sacrificed, which they termed Agnihotra, varied, but very often consisted of dairy products called Pansha Govnya.  Brahmins, the Vedic priests, performed all Vedic sacrifices for the entire community.  Through sacrifice, it was believed, the world would be kept going and it is said that the universe will vanish when the last Brahmin has celebrated the last agnihotra (Yoga and the Hindu Tradition, 75).  Accordingly, Vedic peoples made regular sacrifices to the gods, some assiduous in their duty of offering up every day, night, and morning (75).  Accordingly, Vedic practitioners continually sacrificed in order to keep the world going.

     The renunciation of Vedic principles formed the basis for Yogic tradition.  The Yogis hung onto the idea of ritualized sacrifice bringing on the end of the world, which they termed Pralaya, but they put a unique twist on it.  They believed in Maya, or that the world as they knew it was merely an illusion.  Yogis desired to bring Pralaya closer and to return to what everything came from, called Tad, or the Essence.  The practice of Yoga changed sacrifice from a physical ritual done only by priests to a meditative one consisting of self-sacrifice.  Through Yoga, one practiced using various Tapas, or postures and sensory withdrawal, as a means to reach higher consciousness.  Yogis reached their aspirations because the [t]apas (ascetic virtue) thus consists in mastering ones desires in order to transcend this dialectic, which is seen as a manifestation of sarvam duhkham (all is suffering). (Yoga and the Hindu Tradition, 102).  In this, Yogis reflected their new outlook based on the desire to return the world to its original state by going beyond the Maya to return to the essence.

     The Laws of Manu sought to synthesize the Vedic and Yoga traditions.  The Laws of Manu laid out its methods in the Four Aims and the Four Stages.  The Four Aims integrated the necessity for pleasure, as well as Vedic ideals of obligation, followed by the eventual reaching of Yogic Moksha, or liberation, the freeing of the captive soul from phenomenal existence (Yoga and the Hindu Tradition, 235).  The Four Stages yet again paralleled a youthful yet obligatory Vedic-like life, followed by solitude and renunciation a common practice of Yogis.  In this, the Laws of Manu once again used self-sacrifice in the form of yoga as a means to reach Moksha thus returning to the essence.

     The Bhakti tradition began in approximately 400 AD, and its practitioners sought communion with god.  This god was most often Vishnu, the sustainer god.  Bhakti practitioners made ritualized sacrifices similar to Vedic ritual, but instead of sacrifice using fire, Bhakti tradition taught sacrifice made to icons.  This new use of icons developed because the emphasis on devotion offered to one particular deity fostered the use of plastic representations (The Hindu Tradition, 119).  Darshan, as they termed it, was the practice of visualizing and forcing the deity into the icon to receive the offerings, or puja.  Followers of Hindu Bhakti religion sought salvation through an ardent and passionate love for God, and through this they sought to reach a communion with god in hopes that they would eventually reside with that god for eternity (The Hindu Tradition, 261).

Tantra began at a similar time to Bhakti, but was very different.  Whereas Bhakti taught communion with god, Tantric followers wanted to themselves transform into a divinized form.  Tantric practitioners often worshipped Shiva, the destructor god, or the goddess.  Tantra was unique in that

one of the many methods of gaining salvation advocated by Tantras is the ritual use of forbidden, or normally unlawful, acts, such as the eating of meat, the drinking of liquor, or promiscuous sexual intercourse, as a religious rite.

which was similar to what the original Vedas praised (The Hindu Tradition, 233).  Tantra, however, uses these acts as a means of releasing shakti, or energy, as a method of sacrifice.   Through this the worshipper asserts the oneness of all life, even those aspects usually considered unclean. (233).

     There are also many other variations on Hindu sacrifice. The modern spiritual teacher Osho speaks of meditation and of what he calls a cross-cultural community.  The ritualistic Aghori spend years at cremation grounds, eating little and using ashes in hopes of enlightenment.  Some use celebratory lights and dance.

     The Yogis, through their inward and individualistic self-sacrifice most genuinely accomplished sacrifice, because they alone took it unto themselves to save themselves.  This took much time and concentration, as opposed to simply giving up physical objects for sacrifice.  It is much harder to introspect for years than to give up items or practice unclean, and generally enjoyable, acts.

     The various goals of each era in Hinduism reflect their methods of sacrifice.  Vedic peoples sought sacrifice through fire as a means to continue the world.  Yogis sought to self-sacrifice through yoga in hopes of returning to the essence and bring pralaya.  The Laws of Manu synthesized the two, but accepted the yogic ideal of returning to the essence.  Bhakti practioners sought to sacrifice through icons using Dharshan in hopes of reaching a communion with god.  Tantra taught ritualizing unclean acts to release energy, and elevate the practitioner into a godlike state.  Through the various ages of Hinduism, sacrifice has become a unifying and evolving theme.