Yevamot 30

Why do I need this mishnah?


e now find ourselves midway through the third chapter of Yevamot. We opened this chapter with a series of mishnahs about the hypothetical case of four brothers, two of whom married sisters and then subsequently died childless, leaving both sisters as potential yevamot of the remaining two brothers. After that, we moved on to a series of mishnahs about three brothers, two of whom married sisters.

Each of these mishnahs presents a slightly different problem that, as the rabbis expertly show us, teases out unique aspect of the laws of levirate marriage. Together, these cases test the nature and boundaries of forbidden relationships (and how those might change with the end of marriage — by death or divorce) as well as the legal status of different steps in the levirate process (from levirate bond through betrothal and finally completed marriage). At the bottom of today’s page, we encounter another interesting gray area — uncertain betrothal and marriage.

You may be asking yourself: Do we really need all of these cases? Indeed, on today’s page, even the rabbis themselves wonder about this. This comes up in the case of two mishnahs that present exceptionally similar cases. In the first, two brothers marry two sisters while a third brother marries an unrelated woman. One of the brothers married to sisters dies childless so the brother who was married to an unrelated woman performs levirate marriage with the widow. Then this brother, now married to two women, also dies childless leaving one remaining brother with two potential yevamot — one of whom is the sister of his wife. The mishnah says both women are now dismissed — the first because she is the sister of the living brother’s wife, and the second because she is the co-wife of the first. But if the second brother had performed only levirate betrothal, then instead the unrelated woman performs halitzah.

In the second mishnah, we again have three brothers, two of whom married sisters and one who married an unrelated woman. But in this case, it is the brother married to the unrelated woman who dies childless. Now one of the brothers married to sisters takes on the widow and subsequently dies childless. This leaves us in a similar position: One remaining brother and two potential yevamot, one of whom is the sister of his wife. A similar solution is offered: Both potential yevamot are dismissed — unless of course the second brother only performed levirate betrothal, in which case the unrelated woman performs halitzah.

You may now be thinking exactly what the Gemara is: 

Why do I need this second mishnah? The principle is identical.

Indeed, the end scenario is identical — as is the legal answer. So why do we need the second mishnah?

One might expect that the rabbis will unearth a fine legal distinction between these two cases, or perhaps posit that different circumstances surround the two cases. Instead, they offer a very different explanation for the redundancy:

The tanna (early rabbi) taught this (second) mishnah at first, and with regard to that previous case saw it fitting to render her permitted, and he permitted. And then the tanna subsequently retracted and saw it fitting to render the woman forbidden. 

Originally, the Gemara explains, the tanna who taught the second mishnah taught something different than what we just read! He taught that when the second brother died, the wife who was not the sister of the remaining brother was permitted to him. She was not discounted because of her co-wife (the living brother’s sister). This made both mishnahs necessary, as they taught similar cases with different legal rulings.

However, the tanna subsequently changed his mind and decided the non-related woman was forbidden to the third brother on account of her co-wife in both scenarios — which is why the mishnah now reads the way it does. It also means that both mishnahs end up teaching essentially the same thing. So why, then, do we still have the second mishnah, now rephrased to reflect the tanna’s change of heart? Two reasons:

Since it was beloved to him he taught it first and a mishnah does not move from its place. 

The tanna was attached to the case and for that reason taught it first, before the previous mishnah that, when taught first, renders this one redundant. The other reason, the Gemara explains, is that a mishnah, once fixed, is not removed. And so this beloved mishnah ⁠— which once taught something novel but, since its original teacher had a change of heart was rendered redundant ⁠— lives on. It is now taught under the other teaching, and while it doesn’t teach us something novel about levirate marriage, it does tell us something profound about how the rabbis approached their learning.

Read all of Yevamot 30 on Sefaria.

This piece originally appeared in a My Jewish Learning Daf Yomi email newsletter sent on April 6th, 2022. If you are interested in receiving the newsletter, sign up here.

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Kiddushin 51

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