Matriliny and monogamy
Patriliny (also known as patrilineality or agnatic kinship) is a system in which one belongs to one's father's lineage; it generally involves the inheritance of property, names, or titles through the male line as well.
A patriline is a line of descent from a male ancestor to a descendant (of either sex) in which the individuals in all intervening generations are male. In a patrilineal descent system, an individual is considered to belong to the same descent group same as his or her father. This principle contrasts with the less common pattern of matrilineal descent.
In the world of the Hebrew Bible, the line of descent for monarchs and leading personalities was almost exclusively through the male. Tribal descent, such as whether one is a kohen or a Levite, is still inherited patrilineally in Judaism, as is communal identity as a Sephardi or Ashkenazi Jew.
The norm of patriliny was quite naturally maintained in Christianity, as seen in the genealogies of Jesus, which emphasize his David descent.
This situation contrasts with the rule for inheritance of Jewish status in the Normative Judaism of the Talmud, which is matrilineal.
The Talmud (Kiddushin 68b), in a stratum dating from the 4th-5th centuries, claims that the law of matrilineal descent derives from the Torah. The Torah passage (Deut. 7:3-4) reads: "Thy daughter thou shalt not give to his son, nor shalt thou take his daughter to thy son. For they will turn away thy son from following me, that they may serve other gods." To be sure, this interpretation of the Deuteronomy passage seems contestable. This view was anticipated in the Mishnah (Kiddushin 3:12), where it is stated that, to be a Jew, one must be either the child of a Jewish mother or a convert to Judaism. However, this interpretation did not become general until somewhat later. Despite the seeming support of Scripture, this stipulation of matriliny is an innovation that stands in stark contrast to the patriliny that pervades the Tanakh.
Thus, by the time of the emperor Justinian (527-565) the rabbis had come to believe that Scripture supported a neoteric practice that they had come to defend, namely matriliny. This view is the source of the common perception that “Jewish law” requires that a Jewish person be born of a Jewish mother.
Some scholars believe that this stipulation of matrilineal descent was enacted in response to intermarriage. Others say that the frequent cases of Jewish women being raped by non-Jews led to the law; how could a raped Jewish woman's child be considered non-Jewish by the Jewish community in which he or she would be raised?
During the Middle Ages a minority stream of rabbinic opinion argued in theoretical terms for a rule that, to be Jewish by descent, both one's parents must be Jewish. In practical terms, however, the matrilineal rule remained unchallenged from Talmudic times until the twentieth century.
We turn now to the other reversal, that of polygamy. Polygamy means that one can have more than one wife, or in the case of women, more than one husband. In historical research, however, the term polygamy is generally employed to designate what is more properly termed polygyny. The traditional terminology will be followed here.
Scriptural evidence indicates that polygamy among the ancient Hebrews, though not extremely common, was not particularly unusual and was certainly not prohibited or discouraged. The Hebrew scriptures document approximately forty polygamists, including such prominent figures as Abraham, Jacob, Esau, and David. Their polygamy is taken as a matter of course, requiring little comment.
Polygamy continued to be permitted in Judaism well into the Middle Ages. Yet here are indications of disapproval among Ashkenazi Jews as early as the tenth century. Since the eleventh century, Ashkenazi Jews have followed the ban of Rabbenu Gershom. Since then monogamy has been the norm for them.
Why was this change instituted? Christian pressure undoubtedly had something to do with it, particularly since, under the impact of the Gregorian reforms, the Catholic clergy was insisting on more thorough adherence to sexual and family norms among the flock. The ban on polygamy among the Jews of Eastern Europe may also have reflected the relative scarcity of Jewish women. One could not allow a few alpha males to control more than their share of wives, especially in view of the rulings, a half-millennium before, that having a Jewish mother was a prerequisite for Jewishness.
This disapproval was slow to penetrate among Sephardi and Mizrahi Jews. Those of Yemen and Iran discontinued polygamy quite recently, as the emigrated to countries where it was forbidden. The ban on polygamy may have entered the Mediterranean Jewish world through the French regime in Algeria. There, a law of 1870 made the local Jews became French citizens, requiring that they follow the civil law of the French republic, which does not permit polygamy. Algerian Muslims retained their own laws and customs.
As we know, polygamy was the norm in classical Islam, at least for those who could afford it. While this custom may reflect in part Jewish precedent, it probably derives from the general prevalence of polygamy in the Middle East.
The situation was different in Early Christianity. Or was it? Most of the apostles had wives. Could some have had more than one? This is speculation, and the likelihood is that the circle of Jesus adhered to the official Roman insistence on monogamy.
In the nominally Christian Germanic kingdoms of western Europe, a kind of informal polygamy survived for a time, at least among the elite. Charlemagne had four wives and four concubines. Relations with the wives apparently did not overlap, but with the concubines they almost certainly did.