(Mishnah - R. Eliezer): One who is Mekanei (warns his wife not to be secluded) must do so in front of two witnesses. He can be Mashkeh her (force her to drink Sotah water, or forfeit her Kesuvah) if he or one witness saw her in seclusion;

R. Yehoshua says, Kinuy is in front of two witnesses. Two witnesses of seclusion are needed for Hashka'ah.

What constitutes warning? If he told her in front of two witnesses 'do not speak with Ploni', and she spoke with Ploni, she does not become forbidden to her husband or to eat Terumah;

If she was secluded with Ploni for the time needed for Bi'ah, she is forbidden to her husband and to Terumah;

If her husband died later (without children), she does Chalitzah. She may not do Yibum.

(Gemara) Question: Why does tractate Sotah follow Nazir?

Answer: This is like Rebbi taught:

(Beraisa - Rebbi): The Torah discusses Nazir after Sotah, to teach that anyone who sees a Sotah in her disgrace should become a Nazir.

Question: If so, Sotah should precede Nazir!

Answer: Perek ha'Madir (which discusses vows) is in Tractate Kesuvos, therefore Nedarim follows Kesuvos. Nazir is like a Neder, so it comes next. Sotah follows, for Rebbi's reason.

'One who is Mekanei' connotes that this should not be done.

Our Tana holds that it is forbidden to warn one's wife.

(Reish Lakish): Hash-m arranges matches so that a man always gets a woman commensurate with his deeds - "a Rasha (an evil wife) will not rule over Tzadikim"

(Rabah bar bar Chanah): Arranging matches is harder than Keri'as Yam Suf.

Question (against Reish Lakish): Rav Yehudah taught that 40 days before a fetus is formed, a voice from Heaven announces whose daughter is for him to marry, and which house and field are for him! (Rashi - it is not decreed if they will be Tzadikim or Resha'im, this is up to their free choice!)

Answer: Rav Yehudah's teaching applies to one's initial match. Reish Lakish discusses a second match.

(Mishnah - R. Eliezer): Two witnesses are needed to warn...

The Tana'im argue only about seclusion, but agree that one witness is believed to say that she had Bi'ah.

Support (Mishnah): If one witness saw that she had Bi'ah, she does not drink.

Question: What is the source that the Torah believes one witness to say this?

Answer (Beraisa): "V'Ed Ein Bah (and she was not forced)" - there are not two witnesses (about Tum'ah, only one, and she is forbidden)!

Suggestion: Perhaps it means that not even one witness knows about her!

Rejection: "One witness will not rise against a man."

Question: We already know that the verse discusses one witness, for "Yakum" (rise) is singular. Why did the Torah specify "one"?

Answer: This teaches that everywhere in the Torah "Ed" refers to two witnesses, unless the Torah specifies 'one,'

Summation of answer: The Torah said that there are not two witnesses, only one, and if she was not forced, she is forbidden.

Question: If not for "one witness will not rise", we would have said (c:1) that there is not even one witness of Tum'ah. If so, how would she become forbidden?

Answer: If not for "one witness will not rise", we would have explained "V'Ed Ein Bah" to mean that one witness is not believed to say that she had Bi'ah.

Question #1: If we required two witnesses about Tum'ah, the Torah would not have written anything here, and we would learn from a Gezeirah Shavah "Davar-Davar" from monetary cases that we require two witnesses, like all testimony! (Regarding adultery it says "Ki Matza Vah Ervas Davar.")

Answer: Sotah is different;

Since there are grounds to believe that she had Bi'ah, i.e. he warned her and she was secluded, one would have thought that even one witness about Tum'ah is believed.

Question #2: How could we have thought that the verse teaches that one witness of Tum'ah is not believed and she is permitted? It says "she was not forced", i.e. she is forbidden!

Answer: We would have thought that one witness about Tum'ah is not believed, and she is permitted, unless two witnesses testify about her. And even when two testify, they must say that she was not forced, or else she remains permitted.

(Mishnah): R. Yehoshua says, he warns her in front of two witnesses...

Question: What is R. Yehoshua's reason?

Answer: "(There is no witness) about her (Tum'ah, i.e. adultery)" - about her (Tum'ah one witness suffices) but not about her warning, and not about her seclusion (for these, two witnesses are required).

R. Eliezer expounds about her (Tum'ah, one witness suffices), but not about her warning (this requires two witnesses).

Question: Why doesn't he (also) expound, about her (Tum'ah), and not about her seclusion?

Answer: Seclusion is equated to Tum'ah (for which one witness suffices) - "she was secluded, and became Temei'ah."

Question: Warning is also equated to Tum'ah - "he warned his wife, and she became Temei'ah"!

Answer: The Torah taught that one witness is not enough for warning - "about her" (Tum'ah, but not about her warning).

Question: Why do we equate seclusion to Tum'ah, and exclude warning, and not vice-versa?

Answer #1: Presumably, seclusion is more severe, for it forbids her (to her husband and Terumah), like Tum'ah.

Objection: No, warning is more severe, for through warning, seclusion forbids her!

Conclusion: Neither is more severe, for warning without seclusion does nothing, and seclusion without warning is meaningless.

Answer #2: Seclusion is more severe, for it is the start of Tum'ah.

Our Mishnah is unlike the following Tana.

(Beraisa - R. Yosi b'Rebbi Yehudah, citing R. Eliezer): One warns his wife in front of one witness, or by himself. Two witnesses of seclusion are needed to obligate her to drink.

Chachamim: If so, there is no end! (This will be explained.)

Question: What is R. Yosi's reason?

Answer: "About her (Tum'ah)", and not about her seclusion.

Question: Why doesn't he (also) expound 'about her (Tum'ah), and not about her warning'?

Answer: Warning is equated to Tum'ah - "he warned his wife, and she became Temei'ah."

Question: Seclusion is also equated to Tum'ah - "she was secluded and became Temei'ah"!

Answer: That teaches that the duration of time for seclusion is the time needed for Tum'ah.

(Beraisa - Chachamim): If so, there is no end!

Question: Why is this?

Answer: He can lie, and say that he warned her when he really didn't.

Inference: (This is difficult for R. Eliezer according to R. Yosi, but according to R. Eliezer's opinion) in the Mishnah, he cannot make her drink through lying.

Objection: He can falsely claim that she was in seclusion! (In the Mishnah, R. Eliezer does not require witnesses of seclusion.)

(R. Yitzchak bar Yosef): Chachamim said 'even' according to (you,) R. Yosi, there is no end.

Inference: 'Even' connotes that all the more so, according to the Mishnah there is no end.

Objection: To the contrary! According to the Mishnah, the basis (warning) must be true. According to R. Yosi, he can lie about the basis!

Correction (R. Yitzchak bar Yosef): Rather, (according to R. Eliezer) according to R. Yosi b'Rebbi Yehudah, and even according to the Mishnah, there is no end.

(R. Chanina from Sura): Nowadays, one should not tell his wife not to be secluded with a particular man.

Perhaps the Halachah follows R. Yosi b'Rebbi Yehudah, that he can warn her alone. If she is secluded with him, since she cannot drink, she becomes forbidden forever!

Question (Reish Lakish): What does Kinuy (warning) mean?

Answer #1 (Reish Lakish): It is something that brings enmity between her and others.

Inference: He holds that the husband can warn her himself. She will avoid seclusion with the men she was warned about. They will not know about the warning, and will resent this!

Answer #2 (Rav Yemar bar R. Shalmiya): It is something that brings enmity between him and his wife.

Inference: He holds that warning must be in front of two witnesses. Others will know of the warning (and will not resent her). She will resent her husband's suspicion of her, and will quarrel with him.