Mishnayos Sotah Perek 5 Mishnah 1

Just as the water evaluates her fidelity, so too, the water evaluates his, i.e., her alleged paramour’s, involvement in the sin, as it is stated: “And the water that causes the curse shall enter into her” (Numbers 5:24), and it is stated again: “And the water that causes the curse shall enter into her and become bitter” (Numbers 5:27). It is derived from the double mention of the phrase “and…shall enter” that both the woman and her paramour are evaluated by the water. Furthermore, prior to her drinking the water, just as she is forbidden to her husband, so too is she forbidden to her paramour, because in contrast to the verse stating: “Is defiled [nitma’a]” (Numbers 5:14), a superfluous conjoining prefix vav is added to a later verse, rendering the phrase: “And is defiled [venitma’a]” (Numbers 5:29). The addition indicates another prohibition, that of the woman to her paramour. This is the statement of Rabbi Akiva. Rabbi Yehoshua said: That was how Zekharya ben HaKatzav would interpret it, i.e., he also derived from the superfluous vav that the woman is forbidden to her paramour. Rabbi Yehuda HaNasi says an alternate source: The two times that the defilement of the wife is stated in the passage, namely: “And he warns his wife, and she is defiled” (Numbers 5:14), and the later verse: “When a wife, being under her husband, goes astray and is defiled” (Numbers 5:29), indicate that her defilement results in two prohibitions. One is that she is forbidden to her husband and one is that she is forbidden to her paramour.

כְּשֵׁם שֶׁהַמַּיִם בּוֹדְקִין אוֹתָהּ, כָּךְ הַמַּיִם בּוֹדְקִין אוֹתוֹ, שֶׁנֶּאֱמַר (במדבר ה) וּבָאוּ, וּבָאוּ. כְּשֵׁם שֶׁאֲסוּרָה לַבַּעַל, כָּךְ אֲסוּרָה לַבּוֹעֵל, שֶׁנֶּאֱמַר (שם) נִטְמְאָה, וְנִטְמָאָה, דִּבְרֵי רַבִּי עֲקִיבָא. אָמַר רַבִּי יְהוֹשֻׁעַ, כָּךְ הָיָה דוֹרֵשׁ זְכַרְיָה בֶן הַקַּצָּב. רַבִּי אוֹמֵר, שְׁנֵי פְעָמִים הָאֲמוּרִים בַּפָּרָשָׁה אִם נִטְמְאָה נִטְמָאָה, אֶחָד לַבַּעַל וְאֶחָד לַבּוֹעֵל: