In the follow-up to his remarkably successful book The Know-It-All, in which he spent a year reading the entire Encyclopedia Britannica, A. J. Jacobs decided that he would test what is required of observant Jews in A Year of Living Biblically. While the idea is clever, it is based on a faulty assumption. Observant Jews do not live biblically at all. Jews live in accordance with rabbinic interpretation of the Bible, not accordance with the Bible alone. As I frequently teach non-Jews, Judaism is a post-Biblical religion.
Cynics would argue that the Rabbis arrogated to themselves a power denied them by scripture. However, a close reading of several passages proves otherwise. For instance, the Book of Deuteronomy considers what to do when, after conquering the land of Israel, some Israelites find themselves too distant from Jerusalem where, it would seem, the only eating of meat is permitted as part of a sacrificial offering. The text allows for the local slaughter and eating of meat provided that it follows the procedures precisely as God had commanded (Deuteronomy 12:21). However, there is no other statement of these procedures any place else in the Torah. Hence, the text could only be referring to rules that are part of a parallel, oral tradition.
One of the heroes of Jewish history during the amphictyonic period is Gideon who leads the people to victory over the Midianites. Gideon recalls the many wonders Israelite fathers told their children about at the time he is given his mission (Judges 6:13). Note that Gideon does not refer to the plagues or to the Exodus that are specifically detailed in the Torah but to other unspecified “wonders” that go unmentioned. The text itself alerts us to the method by which traditions were passed on.
And it is in God’s charge to Moses before the eighth plague that God confirms the same method. The purpose of the plagues – and Pharaoh’s obstinate refusal to surrender to them – is identified as the subject of future stories that will be transmitted to children and grandchildren (Exodus 10:2).
The orally transmitted stories and explanations complemented the written Torah text, adding new dimensions of flexibility and adaptability that enabled Judaism to respond to new challenges and still remain vital.