Halakhic Rabbit Hole (#2) — BT Yebamot 61b-62a — #73

[61b] Bet Shammai say: two males. What is Bet Shammai’s reasoning? They derive it from [the example] of Moses, as it is written, The sons of Moses: Gershom and Eliezer (1 Chronicles 23:15). And Bet Hillel? They derive it from the creation of the world. And Bet Shammai—[can they not also] derive it from the creation of the world? [No, Bet Shammai says:] We  cannot infer what is possible [62a] from what is impossible. And Bet Hillel—[can they not] derive it from Moses also? [Bet Hillel] would tell you: Moses acted as he did based on his understanding, as it has been taught in a baraita: Moses did three things on the basis of his understanding and [in each instance] his thinking aligned with that of the Omnipresent: [1] He separated from his wife; [2] he broke the tablets; [3] he added one day. 

INTRODUCTION

In TMT #72 we examined a mishnah concerning the Rabbis’ interpretation of Genesis 1:28 (“Be fertile and increase”) which they deemed to be a mitzvah for men (that determination comes  later in the discussion). If God commands men to procreate, it is natural to ask: How many children must one have to fulfill the mitzvah? The mishnah recorded a disagreement between Bet Shammai (B”S) and Bet Hillel (B”H). The former held that a man must father two sons; the latter held that he must have a son and a daughter. The mishnah told us that B”H’s opinion rested on the scriptural basis of Genesis 5:2 (“Male and female God created them”) but supplied no support for B”S’s view. The passage of Gemara above begins by quoting a phrase from the mishnah: “Bet Shammai say: two males.”

COMMENTARY

The Gemara supplies a source for Bet Shammai’s opinion. It tells us that B”S derived their opinion from the example of Moses—singular leader, prophet, law-giver, even rabbi (in the minds of the Sages)—who had two sons Gershom and Eliezer. Could there be any question but that Moses knew God’s will and fulfilled it? The Gemara cites for proof a verse from First Chronicles. Why did it not cite Exodus 18:3–4, where we first learn the names of Moses’ two sons? Perhaps because the Exodus verse comes just after the Israelites cross the Reed Sea where Moses meets Tzipporah, their sons, and Jethro in the wilderness. He has been separated from his wife for some time—perhaps their reunion will result in another child, perhaps a daughter? The First Book of Chronicles, however, is written much later, long after Moses lived, and 23:14 lists two only children: both sons.

Bet Hillel’s reasoning is entirely different. As we saw in TMT #72, the mishnah cited Genesis 5:2: Male and female God created them. Rather than basing the halakhic requirement on the example of Moses, B”H derive it from the creation story: God, the cosmic parent, created Adam and Eve, hence a man should emulate God by creating a son and a daughter.

Gemara often explores a disagreement in halakhic justification, such as this one between B”S and B”H, by asking: How would they respond to the other’s reasoning? That is precisely what happens next.

The Gemara wonders: Why didn’t Bet Shammai argue from Creation? Gemara speculates that B”S would respond that B”H’s scenario does not apply except in the Garden of Eden case. There, God made one man and one woman to insure that the human species could propagate. (The mishnah’s “impossible” inference is the continuation of the human species had God created two men.) In our world, parents who have two sons and no daughters need not worry about their sons finding mates. (The “possible” inference is the situation in our world, populated with men and women.) 

Next, the converse: Gemara asks why B”H did not derive their view from the example of Moses, as did B”S. The response is that Moses did not stop having children because he thought he had fulfilled the halakhic requirement to Be fertile and increase, but rather because he deemed it necessary and appropriate to separate himself from his wife at that particular juncture in history. In fact, the Gemara says, this was the first of three decisions that Moses made on the basis of his own understanding. The second decision was breaking the stone tablets he received from God on Mount Sinai; the third was to add a day to the two days of abstinence God ordained prior to Revelation.

Gemara will discuss Moses’ three decisions at some length, and so will we in TMT #74. You might enjoy reading Exodus 32 for the background to the second decision, and see if you can find a discrepancy between  Exodus 19:10–11 and Exodus 19:15 that lies behind Gemara’s report of Moses’ third decision.

QUESTIONS TO CONSIDER AND DISCUSS

1. B”S based their view on the example of Moses; B”H based their view on God’s Creation. What do you think the implications are for following the model of Moses versus the model of God in the matter of how many children one is required to bring into the world?
2. If people were to have children until they achieved the standard of either B”S or B”H, no doubt many would have large families, but would it have any effect on the overall balance of males and females in society? 
3. Both B”S and B”H require a man to produce a male child, and neither says that two daughters fulfills the mitzvah of procreation. What are your thoughts on the social and psychological implications of this, both for children and for parents, as well as for society?