Jerusalem Talmud Sotah 8.6

משנה: וּמִי הָאִישׁ אֲשֶׁר אֵירַשׂ אִשָּׁה וְלֹא לְקָחָהּ וְגוֹמֵר. אֶחָד הַמְאָרֵשׂ בְּתוּלָה וְאֶחָד הַמְאָרֵשׂ אֶת הָאַלְמָנָה אֲפִילוּ שׁוֹמֶרֶת יָבָם וַאֲפִילוּ שָׁמַע שֶׁמֵּת אָחִיו בַּמִּלְחָמָה חוֹזֶר וּבָא לוֹ. כָּל אֵילּוּ שׁוֹמְעִין דִּבְרֵי כֹהֵן מֵעֶרְכֵי מִלְחָמָה וְחוֹזְרִין וּמְסַפְּקִין מַיִם וּמָזוֹן וּמְתַקְּנִין אֶת הַדְּרָכִים.

MISHNAH: “ Who is the man who became betrothed to a woman and did not take her,” etc. Not only one betrothed to a virgin, even one betrothed to a widow, even to one who waits for her brother-in-law. Even if he heard that his brother had died in the war he then returns and leaves. All those who listen to the Cohen in the front lines return and provide food and water and improve the roads.

הלכה: אֲשֶׁר אֵרַשׂ אִשָּׁה. אֵין לִי אֶלָּא רוֹבֶה שֶׁנָּשָא רֵיבָה. מְנַיִין רוֹבֶה שֶׁנָּשָׂא אַלְמָנָה. אַלְמוֹן שֶׁנָּשָׂא רֵיבָה. [אַלְמוֹן שֶׁנָּשָׂא אַלְמָנָה] מְנַיִין. תַּלְמוּד לוֹמַר אִשָּׁה. מִכָּל מָקוֹם. מַה תַלְמוּד לוֹמַר חֲדָשָׁה. פְּרָט לַמַּחֲזִיר אֶת גְּרוּשָׁתוֹ. אָמַר רִבִּי יוֹסֵי. זֹאת אוֹמָרָת הַנּוֹשֵׂא אֶת הָאַיְילוֹנִית הוֹאִיל וְאֵין מִצְוָה לֵישֵׁב עִמָּהּ אֵינוֹ חוֹזֵר.

HALAKHAH: “Who became betrothed”. Not only a young man who married a young woman. From where even a young man who married a widow, a widower who married a young woman, a widower who married a widow? From where? The verse says, “a woman”, of any kind. Why does the verse say, “new”? That excludes him who remarries his divorcee. Rebbi Yose said, this implies that one who marries a sheram does not return since he has no religious obligation to live with her.

אֲפִילוּ שׁוֹמֶרֶת יָבָם לַחֲמִשָּׁה אַחִים. וְדִכְוָותָהּ אֲפִילוּ בַּיִת אֶחָד לַחֲמִשָּׁה אַחִין. תַּמָּן אֵין כָּל אֶחָד וְאֶחָד רָאוּי לֵישֵׁב בּוֹ. בְּרַם הָכָא כָּל אֶחָד וְאֶחָד רָאוּי לְיּיַּבֵּם. מַה דָמֵי לָהּ. קִידֵּשׁ אִשָּׁה מֲעַכְשָׁיו לְאַחַר שְׁנֵים עָשָׂר חוֹדֶשׁ וְשָׁלֵם הַזְּמָן בַּמִּלְחָמָה חוֹזֵר וּבָא לוֹ.

Even one who waits for her brother-in-law with five brothers. Similarly, even one house for five brothers? There not one of them would be able to live in it. But here, each one of them is able to marry in levirate. What would be like it? Somebody who preliminarily married a woman from now on in twelve months and the time is up while he is in the war; he returns and goes.