To these laws was prefixed, as an introduction, the priestly history that opens with the account of creation in the first chapter of Genesis and briefly traces Israel's history to the settlement in Canaan. The interest of these late priestly historians is, like that of the Chronicler, in the origin of institutions. Thus the object of the first chapter of Genesis is to give the traditional origin and authority of the sabbath. The account of the flood culminates in a covenant embodying the command that man shall not eat of the blood of sacrificial animals; the priestly stories regarding Abraham aim to give the origin of the rite of circumcision. Israel's early experiences in the wilderness furnish the setting for the giving of the law at Sinai. In this way the late editors of these opening books of the Old Testament connect all of Israel's legislation with Moses and aim to establish its divine authority. V. Their Important Regulations. The central aim in all these late priestly laws was similar to that of Ezekiel: it was to make Israel a holy people and to prevent them from falling again into the sins to which were attributed the overwhelming disasters that had overtaken them. This aim they sought to accomplish: (1) by making the temple and its services the centre of the life of the people and through ceremonial barriers and regulations to shield it from everything that might pollute it; (2) by rendering the temple service attractive; (3) by insuring through rigid ceremonial laws the purity of its priesthood; (4) by preserving the ceremonial cleanliness of the people through strict laws regarding the food which they ate and elaborate provisions for their purification in case they were contaminated by contact with that which was regarded as unclean; (5) by prohibiting absolutely all marriages with the heathen; and (6) by emphasizing the rigid observation of the sabbath and other distinctive institutions. In general these late priestly laws represented a return to the older and more primitive conception of religion, and defined duty in terms of ceremonial rather than moral acts.