Since the rise of the comparative or historical study of religions in the latter part of the 19th century, attempts have been made to discover the origins of sacrifice. These attempts, though helpful for a greater understanding of sacrifice, have not been conclusive.

In 1871 Sir Edward Burnett Tylor, a British anthropologist, proposed his theory that sacrifice was originally a gift to the gods to secure their favour or to minimize their hostility. In the course of time the primary motive for offering sacrificial gifts developed into homage, in which the sacrificer no longer expressed any hope for a return, and from homage into abnegation and renunciation, in which the sacrificer more fully offered himself. Even though Tylor’s gift theory entered into later interpretations of sacrifice, it left unexplained such phenomena as sacrificial offerings wholly or partly eaten by worshippers.

William Robertson Smith, a Scottish Semitic scholar and encyclopaedist, marked a new departure with his theory that the original motive of sacrifice was an effort toward communion among the members of a group, on the one hand, and between them and their god, on the other. Communion was brought about through a sacrificial meal. Smith began with totemism, according to which an animal or plant is intimately associated in a “blood relationship” with a social group or clan as its sacred ally. In general, the totem animal is taboo for the members of its clan, but on certain sacred occasions the animal is eaten in a sacramental meal that ensures the unity of the clan and totem and thus the well-being of the clan. For Smith an animal sacrifice was essentially a communion through the flesh and blood of the sacred animal, which he called the “theanthropic animal”—an intermediary in which the sacred and the profane realms were joined. The later forms of sacrifice retained some sacramental character: people commune with the god through sacrifice, and this communion occurs because the people share food and drink in which the god is immanent. From the communion sacrifice Smith derived the expiatory or propitiatory forms of sacrifice, which he termed piaculum, and the gift sacrifice. There were great difficulties with this theory: it made the totem a sacrificial victim rather than a supernatural ally; it postulated the universality of totemism; and, further, it did not adequately account for holocaust sacrifices in which the offering is consumed by fire and there is no communal eating. Nevertheless, many of Smith’s ideas concerning sacrifice as sacramental communion have exerted tremendous influence.

Sir James George Frazer, a British anthropologist and folklorist, author of The Golden Bough, saw sacrifice as originating from magical practices in which the ritual slaying of a god was performed as a means of rejuvenating the god. The king or chief of a tribe was held to be sacred because he possessed mana, or sacred power, which assured the tribe’s well-being. When he became old and weak, his mana weakened, and the tribe was in danger of decline. The king was thus slain and replaced with a vigorous successor. In this way the god was slain to save him from decay and to facilitate his rejuvenation. The old god appeared to carry away with him various weaknesses and fulfilled the role of an expiatory victim and scapegoat.

Henri Hubert and Marcel Mauss, French sociologists, concentrated their investigations on Hindu and Hebrew sacrifice, arriving at the conclusion that “sacrifice is a religious act which, through the consecration of a victim, modifies the condition of the moral person who accomplishes it or that of certain objects with which he is concerned.” Like Smith, they believed that a sacrifice establishes a relationship between the realms of the sacred and the profane. This occurs through the mediation of the ritually slain victim, which acts as a buffer between the two realms, and through participation in a sacred meal. The rituals chosen by Hubert and Mauss for analysis, however, are not those of preliterate societies.

Another study by Mauss helped to broaden the notion of sacrifice as gift. It was an old idea that man makes a gift to the god but expects a gift in return. The Latin formula do ut des (“I give that you may give”) was formulated in Classical times. In the Vedic religion, the oldest stratum of religion known to have existed in India, one of the Brahmanas (commentaries on the Vedas, or sacred hymns, that were used in ritual sacrifices) expressed the same principle: “Here is the butter; where are your gifts?” But, according to Mauss, in giving it is not merely an object that is passed on but a part of the giver, so that a firm bond is forged. The owner’s mana is conveyed to the object, and, when the object is given away, the new owner shares in this mana and is in the power of the giver. The gift thus creates a bond. Even more, however, it makes power flow both ways to connect the giver and the receiver; it invites a gift in return.

Gerardus van der Leeuw, a Dutch historian of religion, developed this notion of gift in the context of sacrifice. In sacrifice a gift is given to the god, and thus man releases a flow between himself and the god. For him sacrifice as gift is “no longer a mere matter of bartering with gods corresponding to that carried on with men, and no longer homage to the god such as is offered to princes: it is an opening of a blessed source of gifts.” His interpretation thus melded the gift and communion theories, but it also involved a magical flavour, for he asserted that the central power of the sacrificial act is neither god nor giver but is always the gift itself.

German anthropologists have emphasized the idea of culture history, in which the entire history of mankind is seen as a system of coherent and articulated phases and strata, with certain cultural phenomena appearing at specific levels of culture. Leo Frobenius, the originator of the theory that later became known as the Kulturkreislehre, distinguished the creative or expressive phase of a culture, in which a new insight assumes its specific form, and the phase of application, in which the original significance of the new insight degenerates. Working within this context, Adolf E. Jensen attempted to explain why men have resorted to the incomprehensible act of killing other men or animals and eating them for the glorification of a god or many gods. Blood sacrifice is linked not with the cultures of the hunter–gatherers but with those of the cultivators; its origin is in the ritual killing of the archaic cultivator cultures, which, in turn, is grounded in myth. For Jensen the early cultivators all knew the idea of a mythic primal past in which not men but Dema lived on the earth and prominent among them were the Dema-deities. The central element of the myth is the slaying of a Dema-deity, an event that inaugurated human history and gave shape to the human lot. The Dema became men, subject to birth and death, whose self-preservation depends upon the destruction of life. The deity became in some way associated with the realm of the dead, and, from the body of the slain deity, crop plants originated, so that the eating of the plants is an eating of the deity. Ritual killing, whether of animals or men, is a cultic reenactment of the mythological event. Strictly speaking, the action is not a sacrifice because there is no offering to a god; rather, it is a way to keep alive the memory of primeval events. Blood sacrifice as found in the later higher cultures is a persistence of the ritual killing in a degenerated form. Because the victim is identified with the deity, later expiatory sacrifices also become intelligible: sin is an offense against the moral order established at the beginning of human history; the killing of the victim is an intensified act restoring that order.

Another interpretation of some historical interest is that of Sigmund Freud in his work Totem und Tabu (1913; Eng. trans. Totem and Taboo). Freud’s theory was based on the assumption that the Oedipus complex is innate and universal. It is normal for a child to wish to have a sexual relationship with its mother and to will the death of its father; this is often achieved symbolically. In the primal horde, although the sons did slay their father, they never consummated a sexual union with their mother; in fact, they set up specific taboos against such sexual relations. According to Freud, the ritual slaughter of an animal was instituted to reenact the primeval act of parricide. The rite, however, reflected an ambivalent attitude. After the primal father had been slain, the sons felt some remorse for their act, and, thus, the sacrificial ritual expressed the desire not only for the death of the father but also for reconciliation and communion with him through the substitute victim. Freud claimed that his reconstruction of the rise of sacrifice was historical, but this hardly seems probable.

In 1963 Raymond Firth, a New Zealand-born anthropologist, addressed himself to the question of the influence that a people’s ideas about the control of their economic resources have on their ideology of sacrifice. He noted that the time and frequency of sacrifice and the type and quality of victim are affected by economic considerations; that the procedure of collective sacrifice involves not only the symbol of group unity but also a lightening of the economic burden or any one participant; that the use of surrogate victims and the reservation of the sacrificial food for consumption are possibly ways of meeting the problem of resources. Firth concluded that sacrifice is ultimately a personal act in which the self is symbolically given, but it is an act that is often conditioned by economic rationality and prudent calculation.

Most social anthropologists and historians of religion in the mid-20th century, however, concentrated less on worldwide typologies or evolutionary sequences and more on investigations of specific historically related societies. Consequently, since World War II there have been few formulations of general theories about the origin of sacrifice, but there have been important studies of sacrifice within particular cultures. For example, E.E. Evans-Pritchard, a social anthropologist at the University of Oxford, concluded after his study of the religion of the Nuer, a people in South Sudan, that for them sacrifice is a gift intended “to get rid of some danger of misfortune, usually sickness.” They establish communication with the god not to create a fellowship with him but only to keep him away. Evans-Pritchard acknowledged, however, that the Nuer have many kinds of sacrifice and that no single formula adequately explains all types. Furthermore, he did not maintain that his interpretations of his materials were of universal applicability. Many scholars would agree that, though it is easy to make a long list of many kinds of sacrifice, it is difficult, if not impossible, to find a satisfactory system in which all forms of sacrifice may be assigned a suitable place.