משנה: לָזֶה שְׁנַיִם וְלָזֶה שְׁנַיִם אָחִיו שֶׁלָּזֶה חוֹלֵץ לָאַחַת וְאָחִיו שֶׁלָּזֶה חוֹלֵץ לָאַחַת. אָחִיו שֶׁל זֶה מְיַיבֵּם חֲלוּצָתוֹ שֶׁלָּזֶה. וְאָחִיו שֶׁל זֶה מְיַיבֵּם חֲלוּצָתוֹ שֶׁלָּזֶה. קָֽדְמוּ הַשְּׁנַיִם וְחָֽלְצוּ לֹא יְיַבְּמוּ הַשְּׁנַיִם אֶלָּא אֶחָד חוֹלֵץ וְאֶחָד מְייַבֵּם. קָֽדְמוּ וְכָֽנְסוּ אֵין מוֹצִיאִין מִיָּדָם. MISHNAH: If each [of the deceased] had two brothers, one brother of each [of the deceased] performs ḥalîṣah with one [of the sisters] and the other brother takes the other [sister] in levirate162If the ḥalîṣah of his brother was correct, then the other brother marries an unrelated widow. If it was incorrect then he enters a valid levirate marriage.. If two [brothers] both performed ḥalîṣah163Each of them for another woman., the other two should not [both] marry in levirate164Since one of them might marry the sister of a candidate of levirate with him. But if they married without asking, one of them certainly executed a valid levirate and the other married an unrelated woman. but one of them performs ḥalîṣah and the other one may take in levirate. If both married without asking, one does not remove [the women] from them.
הלכה: לָזֶה שְׁנַיִם וְלָזֶה שְׁנַיִם כול'. הָדָא דְאַתְּ אָמַר בְּיִשְׂרָאֵל אֲבָל בְּכֹהֲנִים אָסוּר. HALAKHAH: “If each [of the deceased] had two brothers”. That is, for Israel, but for Cohanim they are forbidden165If the first pair of brothers both performed ḥalîṣah and the second are Cohanim then one of the second pair certainly will marry a woman freed by ḥalîṣah, who is considered a rabbinic divorcee. The Babli, 24a, seems to extend the permission given to Cohanim (Note 159) even to this case since for each single person there is only a 50/50 chance that he married a woman with a legally valid ḥalîṣah..