The power of blood in belief and superstition has often been the subject of ethnographic discussion. Among the Greeks what is striking is, if anything, a certain reticence towards blood magic; there is nothing of a universal blood taboo as in the law of the Jews. Animal sacrifice is the shedding of blood; that the altars become bloody (haimassesthai) is a characteristic of the sacrificial act. On vase paintings there are white-chalked sides of the altars that are always shown splashed with blood in testimony to the sacred work. An altar in Didyma is said to be made from the blood of the victims.
Significantly, the victims which are pleasing to the Gods are warmblooded animals, mostly large mammals; fish, though much more important for everyday sustenance, are rarely if ever sacrificed. What counts is the warm, running blood which arouses fear and suspicion. Non-bloody sacrifices are described with special emphasis as pure. The sacrificer however, is not in some sense impure, but enjoys a sacred, exceptional status in accordance with the divine ordinance which sanctions and demands the shedding of blood at the sacred pot.
Of course today this isn’t really necessary unless you use your own blood without killing yourself. For this reason a man who sits on or next to a altar cannot be killed or harmed; this would be a perversion of the sacred and would inevitably plunge the whole city into ruin. The asylum of the altar stands in polar relation to the shedding of blood; the shedding of human blood constitutes the most extreme, yet dangerously similar contrast to the pious work.
In a number of cults human blood is shed. This human sacrifice can be traced back to the barbaric origins as to the dark ages of the Greek history. The image of the Taurian Artemis, which is presided over the human sacrifices in Kolchis and was later brought to Greece by Orestes along with Iphigeneia, is mentioned in particular as provoking as such rites. It is said to be preserved in Halai Araphenides in Attika where at the sacrifice for Artemis Tauropolos a man has his throat scratched with a knife or else with Ortheia in Sparta where the epheboi are whipped at the altar.
There are sacrificial rituals in which the shedding of blood appears to be carried out for its own sake and not as the prelude to a meal. This type of blood sacrifices can be found in two extreme situations, before battle and at the burial of the dead; the other context in which they occur is at purification. Before battle the Spartans slaughter a goat for Artemis Agrotera, usually, however, the reports mention no god, but just the fact that on the battlefield, in view of the enemy, the general or the seers who accompany the army will cut the throats of animals; whole herds are driven along for this purpose. From certain signs in the victims the seers determin the prospects of success in the battle. The quasi-harmless and manageable slaughter is a premonitory anticipation of the battle and its unforeseeable dangers. It is a beginning.
It is said that before the battle of Salamis, the captured Persians were sacrificed in place of the animals. Myth knows many variants of the ideally willing sacrifice of maidens before battle; Iphigeneia of Aulis can also be placed in that category. In Aeschyles’ Seven against Thebes the threatening anticipation of bloodshed is presented as a binding oath: before the walls of Thebes, the Seven slaughter a bull ‘into a black-rimmed shield’, touch with their hands the blood of the bull, and swear ‘by Ares, Enyo and bloody Terror’ to win or die. Otherwise rites of blood brotherhood and the communal drinking of blood are generally attributed to barbarians or groups at the edge of society.
At the burial of the dead, animals are slaughtered and burned ont he funeral pyre. At the funeral pyre of Patroklos, Akhilles slaughters many sheep and oxen, four horses, two dogs and 12 captured Trojans. This can be understood as an outburst of helpless fury: ‘if you are dead, the others should not live’. Nevertheless, when it is related that ‘about the dead man flowed blood to reach the dead man in some way, to give him back life and colour; red colouring is used in burials as early as the Paleolithic. Sacrifices of this kind are also repeated in honour of the dead man. Here no altar is set up; but a pit is dug in the ground, into which the blood flows. The idea arises that the downward flowing blood reaches the dead: ‘satiating with blood’. In the earliest texts of literature, this is used to conjure up the dead man.