Linguistic survivals make it certain that the part of the sacrifice destined for the god was looked upon as his real food. This conception became offensive with the progressive dematerialization of the deity, and was avoided by offering the deity only the liquid part of the meal. Later the use of fire, which made the sacrificial flesh ascend in smoke from the altar, made it possible to prepare human food in such a way that it was more suitable for the deity. The drink sacrifice was originally the blood of the sacrificed animals; wine was used later as a substitute for the blood. Primitive man looked upon wine as the “blood of the grape”, as our poets still call it. The oldest form of sacrifice, older than the use of fire and the knowledge of agriculture, was therefore the sacrifice of animals, whose flesh and blood the god and his worshippers ate together. It was essential that both participants should receive their shares of the meal. Such a sacrifice was a public ceremony, the celebration of a whole clan. As a matter of fact all religion was a public affair; religious duty was a part of the social obligation. Sacrifice and festival go together among all races; each sacrifice entails a holiday and no holiday can be celebrated without a sacrifice. The sacrificial festival was an occasion for joyously transcending one’s own interests and emphasizing social community and community with god. The ethical power of the public sacrificial feast was based upon primal conceptions of the meaning of eating and drinking in common. To eat and drink with some one was at the same time a symbol and a confirmation of social community and of the assumption of mutual obligations; the sacrificial eating gave direct expression to the fact that the god and his worshippers are communicants, thus confirming all their other relations. Customs that to-day still are in force among the Arabs of the desert prove that the binding force resulting from the common meal is not a religious factor but that the subsequent mutual obligations are due to the act of eating itself. Whoever has shared the smallest bite with such a Bedouin, or has taken a swallow of his milk, need not fear him any longer as an enemy, but may be sure of his protection and help. Not indeed, forever, strictly speaking this lasts only while it may be assumed that the food partaken remains in the body. So realistically is the bond of union conceived; it requires repetition to strengthen it and make it endure.