The life force is what counts...

"Ethnographic and historic examples such as the private farms, temples and public structures in Romano-British England where foundation deposits of animals and infants have been found suggest the release of a life force, anima, or last living breath is important to have value as a sacrifice, rather than the deposit of an already lifeless body (Green 2001). In order to create reciprocal relationships with deities or ancestors, consecrate spaces, or bring about apotropaic effects, the release of the life force or living blood spilled is usually necessary in rituals where human beings or animals are the “gift” or supernatural intermediary."—Sharon Moses in Sacred Killing , page 72

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There is a sermon in there somewhwere...
This book is fascinating. If you are interested in the latest theories about sacrifice, this is "must-have" book.
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