We begin with the Mishnah at the bottom of דף ק״ח עמוּד ב:
הַמְגָרֵשׁ אֶת הָאִשָּׁה וְהֶחְזִירָהּ — מוּתֶּרֶת לַיָּבָם – With regard to one who divorces a woman and remarries her and then dies childless, his wife is permitted to enter into יִבּוּם with her yavam, except according to רַבִּי אֶלְעָזָר who prohibits it.
וְכֵן הַמְגָרֵשׁ אֶת הַיְּתוֹמָה וְהֶחְזִירָהּ — מוּתֶּרֶת לַיָּבָם. וְרַבִּי אֶלְעָזָר אוֹסֵר – Likewise, with regard to one who divorces an orphaned minor girl whose mother and brothers married her off and remarries her and subsequently dies, she is permitted to enter into יִבּוּם with the yavam, except according to רַבִּי אֶלְעָזָר who prohibits it.
קְטַנָּה שֶׁהִשִּׂיאָהּ אָבִיהָ, וְנִתְגָּרְשָׁה — כִּיתוֹמָה בְּחַיֵּי הָאָב. וְהֶחְזִירָהּ — דִּבְרֵי הַכֹּל אֲסוּרָה לַיָּבָם
A minor girl whose father married her off, in which case the marriage is valid by Torah law, and who was subsequently divorced while she was still a minor, is like an orphan during the lifetime of her father (יְתוֹמָה בְּחַיֵי הָאַב), as he no longer has the right to marry her off, and she cannot become fully married because she is a minor. And if the husband remarries her while she is still a minor and then dies childless, everyone agrees that she is forbidden to the yavam and may not enter into יִבּוּם.
The Gemara begins with a cryptic quote from someone named עֵיפָה (Eifah). You won’t him listed in the ArtScroll Introduction to the Talmud’s personalities, nor is there any elaboration here of who he was:
אָמַר עֵיפָה: מַאי טַעְמָא דְּרַבִּי אֶלְעָזָר — הוֹאִיל וְעָמְדָה עָלָיו שָׁעָה אַחַת בְּאִיסּוּרָא. אֲמַרוּ לֵיהּ רַבָּנַן לְעֵיפָה: אִי הָכִי, חֲלִיצָה נָמֵי לָא תִּיבְעֵי
After Eifah is challenged by the רַבָּנַן on his reason for why רַבִּי אֶלְעָזָר took the stringent view in the Mishnah, he quickly backs down and decides that he doesn’t know the reason: אֶלָּא אָמַר עֵיפָה: רַבִּי אֶלְעָזָר לָא יָדַעְנָא מַאי טַעְמָא. Abaye then offers his version of the basis for the opinion of רַבִּי אֶלְעָזָר. And then of course wherever there is Abaye to offer an opinion, there is Rava to serve as the stone to sharpen his saw. They go back and forth before Rav Ashi steps in and opines:
רַב אָשֵׁי אָמַר: הַיְינוּ טַעְמָא דְּרַבִּי אֶלְעָזָר, דְּגָזַר הָנֵי מִשּׁוּם יְתוֹמָה בְּחַיֵּי הָאָב וְהֶחְזִירָהּ. הָכִי נָמֵי מִסְתַּבְּרָא, מִדְּקָתָנֵי סֵיפָא: קְטַנָּה שֶׁהִשִּׂיאָהּ אָבִיהָ וְנִתְגָּרְשָׁה, כִּיתוֹמָה בְּחַיֵּי הָאָב. וְהֶחְזִירָהּ — דִּבְרֵי הַכֹּל שֶׁאֲסוּרָה לַיָּבָם
Rav Ashi said: This is the reasoning of Rabbi Elazar: He prohibits יִבּוּם with women who were divorced and remarried, due to the case of a girl who is considered an orphan in the lifetime of her father (יְתוֹמָה בְּחַיֵּי הָאָב), who was divorced by her husband and he subsequently remarried her. If a minor girl was married off by her father and was subsequently divorced, she is no longer subject to her father with regard to marriage and divorce, but because she is a minor, any marriage she enters into is by rabbinic rather than by Torah law. The Gemara comments: So too, this is reasonable based on what was taught in the latter clause of the mishna: A minor girl whose father married her off and who was subsequently divorced while she was still a minor, is like a יְתוֹמָה בְּחַיֵּי הָאָב. And if the husband remarries her while she is still a minor and then dies, everyone agrees that she is forbidden to the yavam and may not enter into יִבּוּם.
That seems too straightforward for the Gemara’s taste. It therefore concludes as follows:
בַּמֶּה דְּבָרִים אֲמוּרִים — שֶׁגֵּירְשָׁהּ כְּשֶׁהִיא קְטַנָּה וְהֶחְזִירָהּ כְּשֶׁהִיא קְטַנָּה. אֲבָל גֵּירְשָׁהּ כְּשֶׁהִיא קְטַנָּה וְהֶחְזִירָהּ כְּשֶׁהִיא גְּדוֹלָה, אִי נָמֵי הֶחְזִירָהּ כְּשֶׁהִיא קְטַנָּה וְגָדְלָה אֶצְלוֹ וָמֵת — אוֹ חוֹלֶצֶת אוֹ מִתְיַיבֶּמֶת. מִשּׁוּם רַבִּי אֶלְעָזָר אָמְרוּ: חוֹלֶצֶת וְלֹא מִתְיַיבֶּמֶת
In what case is this statement said? In a case where he divorced her while she was a minor and he remarried her while she was still a minor. But if he divorced her while she was a minor and remarried her when she was already an adult, or if he remarried her while she was a minor and she matured to legal adulthood while with him, and he subsequently died, she may either perform חַלִיצָה or יִבּוּם. It was said in the name of R’ Elazar: She must perform חַלִיצָה and may not enter into יִבּוּם, since he decreed that all remarried women may not enter into יִבּוּם due to the case of one who is like יְתוֹמָה בְּחַיֵּי הָאָב.
The bottom line here, as ArtScroll notes, is that there are cases in which the divorcee of the deceased could legally be entitled to do יִבּוּם. But, because the public may not know the distinction is specific cases, R’ Elazar leaned toward the side of stringency to avoid misperceptions, and prohibited יִבּוּם with the divorcee of the deceased in all cases.
You know, we haven’t talked about צָרוֹת in a long time. As a reminder, צָרוֹת are rival co-wives. The Gemara asks:
בְּעָא מִינֵּיהּ רָבָא מֵרַב נַחְמָן: צָרָתָהּ, מַהוּ? אֲמַר לֵיהּ: הִיא גּוּפַהּ גְּזֵירָה, וַאֲנַן נֵיקוּם וְנִיגְזוֹר גְּזֵירָה לִגְזֵירָה
Rava asked Rav Naḥman: What is the halacha with regard to the rival wife of a girl whose husband remarried her, according to R’ Elazar? Is the girl regarded as a forbidden relative to the extent that even her צָרָה may not enter into יִבּוּם? He said to him: She herself is forbidden due to a rabbinic decree, as explained already. And will we then proceed to issue a decree to prevent violation of a decree? Accordingly, her צָרָה is permitted to enter into יִבּוּם. (Another reminder why multiple spouses create צָרוֹת.)
On to the next Mishnh, where we continue to “mix and match” cases:
שְׁנֵי אַחִין נְשׂוּאִין לִשְׁתֵּי אֲחָיוֹת קְטַנּוֹת, וּמֵת בַּעְלָהּ שֶׁל אַחַת מֵהֶן — הַלֵּזוּ תֵּצֵא מִשּׁוּם אֲחוֹת אִשָּׁה. וְכֵן שְׁתֵּי חֵרְשׁוֹת. גְּדוֹלָה וּקְטַנָּה, מֵת בַּעְלָהּ שֶׁל קְטַנָּה — תֵּצֵא הַקְּטַנָּה מִשּׁוּם אֲחוֹת אִשָּׁה
If two brothers are married to two minor sisters, and the husband of one of them dies childless, this widowed girl shall be exempt from יִבּוּם due to her status as a forbidden relative, as one is prohibited from marrying the sister of his wife. The same halacha applies to two deaf-mute women, whose status is like that of two minors in this matter, as their marriages are valid by rabbinic law. And if two brothers were married to two sisters, one of them an adult and the other a minor, and the husband of the minor dies, the minor shall leave due to her status as the sister of a wife, as in the first case in the Mishnah.
This is followed by more considerations about מִאוּן by a minor, when the need for a גֶט arises, and the many continued nuances of יְבָמוֹת. Rabbi Stern will take you the rest of the way.