If you are to look up the term scapegoat, you'll see that it is rooted in sacrifice.
The scapegoat was a goat that was driven off into the wilderness as part of the ceremonies of Yom Kippur, the Day of Atonement, in Judaism during the times of the Temple in Jerusalem. The rite is described in Leviticus 16.
Since this goat, carrying the sins of the people placed on it, is sent away to perish , the word "scapegoat" has come to mean a person, often innocent, who is blamed and punished for the sins, crimes, or sufferings of others, generally as a way of distracting attention from the real causes.
The point here is that the goat, or animal is used to absorb whatever various sins and is sent off to die, or just killed.
Blame the goat.
Sacrifice is just a more abreviated version of this. The animal metaphorically absorbs sins, usually if the animal is more valuable (A bull rather than a goat, a 'perfect' specimen rather than an old or lame one) is would be considered a better sacrifice. This sacrificing, or scapegoating would be to appease whatever anger the gods, or god had toward a group. The Christian bible is filled with many examples of sacrifice to please their god. History, in fact is also full of examples.
What would have more sacrificial value than a human? A pure human.http://en.wikipedia.org/wiki/Human_sacrifice
We see that societies would frequently try to skirt this purity theme by sacrificing alternatives such as captured warriors, or even servants.
When it comes to value though, the virgin is the gold standard. A pure, beautiful virgin.
In ancient Hawai'i, a luakini temple, or luakini heiau, was a Native Hawaiian sacred place where human and animal blood sacrifices were offered.
In Hawaiian mythology, luakini heiaus were first established by Pa'ao, a legendary priest credited with establishing many of the rites and symbols typical of the stratified high chieftainships of the immediate pre-European-contact period. Modern archaeologists no longer believe in a historic Pa'ao, but many Native Hawaiians still believe that he was a historical figure, and often vilify him for introducing what they now see as the bloody, barbarous rites of the luakini heiau.
or a modern sect
Where it is considered illegal by the provincial government, who in a case of staggering irony executes those convicted of human sacrifice. (note:Virtually all state sacrifices are carried out in a ritualistic manner)
What we don't see though, is people eating their sacrifices.
The scapegoats are not cooked and eaten, the bulls are not barbecued and handed out.
The idea here is that the animal has absorbed the sins and transgressions and when they die they take them along.
If you were to eat the scapegoat you'd be just eating the sins and transgressions of the group and thus worse off than before. You'd be cursed so to speak.
Then along came Jesus.
Jesus represents the perfect metaphorical sacrifice.
Pictured: Metaphor. Seriously.
Pure and virginal, check.
Valuable (son of god), check.
So, Jesus, representing the perfect storm of metaphorical value for sins absorbs not just the guilt and sin of those around him but apparently the sin of all mankind and is killed. When he dies he takes all this sin with him and mankind is forgiven.
pictured: Cracker or wafer of flesh?
Then it gets weird.
Remember the part about not eating the sacrifice because it means also eating the absorbed sin?
Well it turns out that one religion does that regularly, through the ritual magic performed weekly called transsubstantiation. Whether the believers think that the crackers and wine are literally transformed, or metaphorically transformed, or merely a metaphor what they are doing flies in the face of the entire concept behind sacrifice.
Even today we can see that the basic idea and metaphorical wishful thinking behind the mechanism of sacrifice remains. What we see though, is an odd throwback via the Catholic church, and in a way Christianity where the supposed benefactors are requred to 're-sorb' the sacrifice.
Pictured above: Resorbing about to occur?