1) TWO WOMEN'S "MEI SOTAH" WHICH WAS MIXED AND THEN DIVIDED
QUESTION: The Gemara discusses a case in which two Megilos Sotah, written for two women undergoing the Sotah process, were erased in two separate cups of Mei Sotah, and then the water in the two cups was mixed together and then divided again into two cups. Is the water effective as Mei Sotah? The Gemara leaves this question unanswered ("Teiku").
The RAMBAM (Hilchos Sotah 4:11) rules that l'Chatchilah one should not use such water, but b'Di'eved if one used it (and neither woman who drank it died) each woman is permitted to her husband.
Why is she permitted to her husband? Since the Gemara concludes that it is a doubt, the principle of "Safek d'Oraisa l'Chumra" should apply and she should remain prohibited to her husband (mi'Safek)! (MINCHAS CHINUCH #365; KEREN ORAH)
ANSWERS:
(a) The OR SAME'ACH (Hilchos Isurei Bi'ah 18:10, DH v'Zeh) suggests that when a woman secludes herself with another man, in a normal situation there is no fear that she committed a sin with him and there is no Safek. She is permitted to her husband because of her Chezkas Heter l'Ba'alah. The only reason why a woman in the situation of a Sotah is prohibited to her husband mi'Safek is that the husband did Kinuy to her -- he warned her not to seclude herself with that man. The fact that he did Kinuy together with the fact that she secluded herself with the man after the Kinuy gives strong reason to believe that she sinned ("Raglayim l'Davar") and thus she is forbidden to her husband mi'Safek.
However, when a Sotah drinks the Mei Sotah, the very fact that she was willing to drink the Mei Sotah and was not afraid of the consequences of her presumed sin annuls the "Raglayim l'Davar," even in the cases in which the Gemara remains in doubt ("Teiku"). Since the woman cannot possibly know for certain that the Mei Sotah is not valid, the fact that she drinks it removes the "Raglayim l'Davar" that she sinned. Therefore, after she drinks her status becomes that of an ordinary Safek, and the Chezkas Heter l'Ba'alah permits her to her husband.
(b) RABEINU CHAIM HA'LEVI explains that "Raglayim l'Davar" alone does not suffice to prohibit a Sotah to her husband (see Insights to Sotah 25:1). This is evident from the fact that the Gemara entertains the possibility that even after a woman secludes herself after Kinuy, her husband can "forgo" the Kinuy of the past and thereby become permitted to her. How, though, can one forgo the "Raglayim l'Davar" which is present due to the Kinuy? Apparently, what prohibits the Sotah to her husband is the combination of the Gezeiras ha'Kasuv of Kinuy and Setirah together with the "Raglayim l'Davar."
Perhaps this Gezeiras ha'Kasuv applies only in the case of a doubt about whether or not the wife sinned, but not to the doubt about the Halachah of whether or not two cups of Mei Sotah that became mixed and re-divided are valid. Therefore, if a woman drinks the re-divided Mei Sotah her status is judged like all other Sefeikos, and the Chezkas Heter l'Ba'alah permits her to her husband. (M. KORNFELD)
2) DRINKING THROUGH A STRAW
OPINIONS: Rava asks whether the Sotah may drink the Mei Sotah through a "Siv" or a "Shefoferes." RASHI defines a "Siv" as a straw. The reason why she should not be permitted to drink the Mei Sotah through a straw is that this is not the normal manner of drinking ("Ein Derech Shetiyah b'Kach"). The Gemara leaves this question unanswered ("Teiku"). (The Rambam omits this law altogether and makes no mention of whether she may or may not drink through a straw. The Acharonim discuss why the Rambam omits it. See CHAFETZ CHAIM in LIKUTEI HALACHOS (Ein Mishpat #50); HE'OROS B'MASECHES SOTAH.)
Does the Gemara imply that this question -- whether or not the act of drinking with a straw constitutes drinking -- has implications for other Halachic matters?
(a) The MAHARSHAM (4:137) suggests that if a sick person needs to drink a forbidden fluid for medicinal purposes, he preferably should drink the fluid through a straw. Since forbidden foods are not Asur mid'Oraisa when consumed in an unusual manner, and the Gemara here considers the possibility that drinking through a straw is not considered "Derech Shetiyah," he should drink the fluid through a straw.
(b) The YOSEF DA'AS suggests that the Gemara's question may be limited to the Mei Sotah, where the Torah says specifically uses the term "v'Hishkah" -- "and he shall give her to drink" (Bamidbar 5:24). The Torah may require that she drink specifically in the normal manner of drinking, "Derech Hashka'ah," and the use of a straw might not constitute the normal manner. For other Halachic matters, however, such as the Torah's prohibition against drinking certain liquids, drinking the liquid through a straw is considered the normal manner of consumption.
The reason for this distinction is that the Torah prohibits the consumption of forbidden items with the term "Achilah." This term does not refer to the specific act of eating a solid as opposed to drinking a liquid, but to the general act of consumption. Even if the food enters one's throat via a straw, it enters his digestive tract and is consumed in the normal manner. In the case of Mei Sotah, the Torah describes the manner in which she must consume the water as an act of "drinking." If the water of the Mei Sotah would be frozen and the ice cut into pieces and given to the woman to eat, her act of eating would not constitute an act of "Hashka'ah," drinking. Similarly, if she consumes the Mei Sotah through a straw and it reaches her throat by bypassing her mouth, it might not be considered an act of "Hashka'ah." (See also SHEVET HA'LEVI 4:21.)

18b----------------------------------------18b

3) HOW DOES THE "MEI SOTAH" PUNISH FOR A FUTURE SIN
QUESTION: In the Mishnah, Rebbi Meir states that when the Sotah accepts the curses ("Alos") she agrees that they will apply to her both if she sinned in the past, and if she will sin in the future. The Beraisa adds that one should not think that Rebbi Meir means that if the woman is going to sin in the future, the Mei Sotah will cause her to die now when she drinks it. Rather, Rebbi Meir means that if she sins in the future, the Mei Sotah she drinks now will take effect and punish her then, at the time she sins.
Why does the Beraisa need to teach that one should not think that the water will cause her to die right now? How is it possible that the water could cause her to die right now because of her future sin? If she dies right now, she obviously will not sin in the future and thus it should not cause her to die!
ANSWER: The TOSFOS HA'ROSH explains that according to Rebbi (6a), who maintains that when a woman drinks the Mei Sotah her Zechus is "Toleh" and delays her punishment even if she sinned, the woman does not immediately die but rather she becomes progressively sicker and weaker until she eventually dies the death which the Torah describes ("Misnavnah"). The Beraisa initially assumed that according to Rebbi Meir, if the woman is going to sin in the future, the Mei Sotah which she drinks now begins its effects upon her by causing her to become sick, "Misnavnah." Later, at the moment she sins, the Mei Sotah exercises its full impact on her and causes her to die. The Beraisa teaches that until she sins the water does not affect her at all. (See PORAS YOSEF for another answer.)

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