Blood sacrifices have a divine origin.
Although Scripture offers few details, it makes it clear that blood sacrifices were first instituted and approved by God. The Bible doesn't indicate that these early biblical characters had a clear understanding of the significance of sacrifice, but God's approval of their blood sacrifices pointed towards the coming of a divine sacrifice that would be given for the salvation of the world. The degree to which our ancestors distorted God's image was reflected in the forms of their religions and the nature of their sacrifices. Pagan sacrifices didn't involve clear symbolic expression of human sinfulness and the need for restoration into relationship with a holy God. Pagan religion was primarily motivated by fear, and sought magical ways to appease the gods and avert their anger.