Meatless edens: from creation to the golden age
Many religions base their beliefs on a beginning with herbivorous humans. The eating of meat, in most of these cases, represents the damnation of mankind.
Greek and roman mythology
Humans were given meat by the Titan, Prometheus. He then also had to give them fire so they could consume it. Ovid and Hesiod refer to a "Golden Age" in which humans avoided the consumption of meat, and every living creature was equal. Its strongest opposition to the eating of animals lies in the belief of transformation, fearing they may consume or kill an animal possessing a human soul.
Jainism
Jains base their religion in the ideas of nonviolence and vegetarianism. They believe that the number of senses a creature can classify the quality of life of the object. Plants only having one sense--touch. This acts as justification for their eating plants.
Hinduism
While not a requirement for Hindus, many practice vegetarianism based on scriptures that compare the skin of the animal to the skin of the son. The Yajur Veda states, "You must not use your God-given body for killing God's creatures, whether they are human, animal or whatever." Their belief in karma also deters meat eating, assuming that harming an animal would result ultimately in pain.
Buddhism
Buddha condemned meat-eating, aligning with their ideals based in nonviolence and compassion. While animal sacrifice was still practiced, he advised against eating meat under three conditions: if they witnessed the animal's death, consented to its death, or knew the animal was being killed for them.
CHristianity
In the Christian beginning of the ideal world, Adam and Eve lived in the Garden of Eden. Humans were displayed as nonviolent and vegetarian until they were corrupted. Christians were advised against the "eating of flesh and the taking of strong drink."