The Origins of the Matrilineal Principle in Rabbinic Law

According to rabbinic law, from the second century to the present, the offspring of a gentile mother and a Jewish father is a gentile, while the offspring of a Jewish mother and a gentile father is a Jew (albeit, according to the Mishnah, amamzer, a Jew of impaired status). Each of these two rulings has its own history, as I shall show below, but it is convenient to group them together under the general heading of the “matrilineal principle.” Anthropologists and sociologists use the termmatrilinealto describe societies in which kinship is determined through the females and not the males. Such societies once existed in ancient Egypt and Mesopotamia, and can still be found in parts of Africa, India, and Polynesia. Although rabbinic society and family law have not yet been studied in the light of modern anthropological and sociological theories, it seems clear that the kinship patterns which characterize matrilineal societies are thoroughly foreign to rabbinic society. With only a few exceptions, rabbinic family law is patrilineal. Status, kinship, and succession are determined through the father. (“The family of the father is considered family, the family of the mother is not considered family,” B.Bava Batra109b.) Why, then, did the rabbis adopt a matrilineal principle for the determination of the status of the offspring of mixed marriages?