We’ve spent 38 pages of this tractate discussing the intricacies of the laws of yibbum with very little comment on how unusual the practice actually is. Today’s daf stops and says: “Wait. Should we even be doing yibbum?!” The Gemara’s answer is complicated.
The Gemara starts its discussion by quoting a mishnah in Tractate Bekhorot:
The mitzvah of levirate marriage takes precedence over the mitzvah of halitzah. Initially, they (men performing levirate marriage with their late brother’s wives) would have intent for the sake of the mitzvah. Now, that they do not have intent for the sake of the mitzvah, the sages say: The mitzvah of halitzah takes precedence over the mitzvah of levirate marriage.
The mishnah starts out by saying that ideally one should perform yibbum rather than halitzah, but then insists that this was only true in the days when men were eager to perform yibbum for the opportunity to do a mitzvah, not just to sleep with their sisters-in-law. In fact, the mishnah concludes that in a world where mitzvot aren’t everyone’s topmost motivation, halitzah is preferred.
So should we even be doing yibbum? According to this mishnah, not really.
The Gemara quotes this mishnah, but then nuances its conclusions:
Rav said: We do not force it.
According to Rav, though the mishnah prefers halitzah, we leave the decision up to the yavam and the yevama. What does this look like in practice?
When they would come before Rav, he would say to them: If you want, perform halitzah, and if you want, consummate the levirate marriage, as the Merciful One makes the matter dependent upon your will, as it says: “And if the man does not wish” (Deuteronomy 25:7) — if he wishes (not to marry her), he performs halitzah; if he wishes (to marry her), he consummates the levirate marriage.
But just when things look clear, the Gemara then complicates the mishnah further by insisting that it is no longer relevant, noting that in later generations the Jews went back to preferring the mitzvah of levirate marriage over the mitzvah of halitzah. Why?
Initially they held in accordance with Abba Shaul, and in the end they held in accordance with the rabbis. As it is taught: Abba Shaul says that: “One who consummates a levirate marriage with hisyevama for the sake of her beauty, or for the sake of marital relations, or for the sake of another matter, it is as though he encountered a forbidden relation, and I am inclined to view the offspring as a mamzer.” The rabbis say: “Her brother-in-law will have intercourse with her” (Deuteronomy 25:5) — in any case.
The Gemara concludes that public practice shifted from agreeing with one rabbi to agreeing with another. And to jump 1,500 years forward, today the Jewish world has shifted again, mandating halitzah instead of yibbum in almost every case.
Sometimes when we are immersed in a situation, we can forget to see the forest for the trees. We can follow the internal logic without stopping and asking: Does any of this even make sense? But today’s daf is a helpful reminder of how important it is when we are immersed in the details of a situation to stop every once in a while, and ask: What are we even doing here?
Read all of Yevamot 39 on Sefaria.