“When the Torah was given, halachah (Jewish law) was renewed.”
The Gemara is discussing the circumstances under which ritual circumcision may be performed on Shabbat. Rabbi Asi asserts that the key factor is whether or not the newborn’s mother was made ritually impure as a result of the birth — if she was (as in the case of vaginal childbirth) a circumcision may be performed on Shabbat when it coincides with the 8th day of the baby’s life; if she wasn’t (as in the case of a caesarian section) the circumcision cannot be performed on Shabbat and is deferred until later.
Rabbi Asi cites Leviticus 12:2-3 a prooftext: If a woman bears seed and gives birth to a male, she shall be impure for seven days . . . and on the eighth day the flesh of his foreskin shall be circumcised. The juxtaposition of the verses creates a legal connection between ritual impurity and circumcision, implying to Rabbi Asi that births that cause ritual impurity require circumcision on the eighth day, even when it falls on Shabbat, while others do not.
Abaye challenges Rabbi Asi, claiming: The early generations will prove that Rabbi Asi’s idea is not valid: in that era childbirth did not render the mother impure and circumcision was on the eighth day.
For Abaye, the “early generations” — i.e. biblical personalities like Abraham and Sarah that lived before the giving of the Torah — offer a legal precedent. Although they lived at a time before the laws of ritual impurity came to exist, they were commanded to perform circumcision on the eighth day (Genesis 17:12), implying that ritual impurity is not a factor in determining whether circumcision is permitted on Shabbat.
Rabbi Asi rejects Abaye’s argument with the following retort: when the Torah was given, halachah (Jewish law) was renewed. Meaning: When the Torah was given, Jewish law was reset. Earlier generations do not provide legal precedent.
Medieval Jewish thinker and legal codifier Moses Maimonides supports Rabbi Asi’s position in his commentary on Mishnah Chullin 7:6, arguing that while biblical narratives that preceded the giving of the Torah may be models for Jewish practice, they are not authoritative sources for determining the particulars of the rabbinic law. This explains why the Talmud is generally untroubled when biblical characters do not conform to rabbinic norms of practice.
Nonetheless, moments when biblical characters act in a fashion that is very un-rabbinic can trouble the rabbis. For example, in a scene that models the rabbinic ideal for welcoming guests, Abraham rushes to furnish three strange visitors with a feast, serving them “curds and milk and the calf that had been prepared” (Genesis 18:8) — an apparent departure from the biblically-mandated Jewish dietary practice of separating milk from meat.
Some commentators are troubled by this verse and find a way to explain Abraham’s actions that bring them into line with their views of normative Jewish practice. The twelfth century commentator Rabbi David Kimhi (also known as Radak) claims that Abraham placed both dairy and meat before his guests so that they could “eat from whichever they wanted.” And a different commentator from the same century, Joseph ben Isaac Bekhor Shor notes that the verse suggests the dairy was served before the meat, bringing the meal in line with the norms of rabbinic kashrut which permits the eating of dairy before meat without a wait time in between.
But many other biblical commentators are silent on this matter and do not seem to be bothered by this verse, perhaps under the assumption that Abraham was not obligated to follow the laws of kashrut — a position which is in line with Rabbi Asi’s.
Contemporary readers of the Talmud, especially those who are engaged in reading Daf Yomi, might be asking questions that parallel the rabbinic debate: in what ways do the rabbis of the Talmud provide a model for Jewish practice today? In what ways has Judaism been transformed by historical events and the experiences of our people? What might justify changing the practices that we inherited from our talmudic ancestors?
There are many ways that contemporary Jews answer these questions. And, as we learn on each and every page of Gemara, there is value in dialogue and in the contemplation of a wide variety of answers.