Why does it say that Torah guards you from an evil woman?
Rashi: Torah guards you from the 'Ishah' of a bad conduct. Surely Shlomo does not discuss an evil woman (Zonah) - is the entire reward and praise of Torah that it guards only from a Zonah?! Rather, this refers to idolatry, which is equal to (as severe as) everything.
R. Yonah: [Zenus] is the head of Aveiros. It brings one to poverty, to the point that he lacks bread (26; Sotah 4b). Chazal warned against excessive talk with Ishto Nidah 1 , lest his Yetzer overpower and he will come to sin. All the more so it applies to another's wife. If we are concerned for Ishto Nidah, that later she will be permitted to him, and he is like one who had bread in his basket, all the more so we are concerned for another's wife; the Yetzer for her is stronger - "Mayim Genuvim Yimtaku" (9:17). It seems that one should not talk excessively with his wife even when she is Tehorah 2 . He is Batel from Divrei Torah (Avos 1:5), for thoughts of Torah are not established when his heart turns to his wife and talk. The heart cannot bear both at once. In the end he inherits Gehinom (ibid.) - since he freely follows his heart to talk extra, in the end he will sin 3 .
Malbim (according to Melitzah): Eshes Ra are Chachmos that lead to denying Elokus.
Magihah: Avos 1:5 says 'even with one's wife'; Rashi and R. Yonah (there) bring from Avos d'R. Nasan (2:1) that this is when she is Nidah.
R. Yonah: This is lest he be [intimate] with her every day. He should not be with her for his pleasure, only to fulfill the Mitzvah. Man must be unlike animals. Chachamim enacted [Tevilas Ezra,] lest Chachamim be frequent with their wives like roosters (Brachos 22a)! This is the Midah of Perishus, which leads to lofty levels - Perishus brings to Taharah (Avodah Zarah 20b). One who talks excessively with his wife causes Ra to himself, i.e. he causes the Yetzer, which is called Ra, to overpower himself. Even Hashem called it Ra - "Ki Yetzer Lev ha'Adam Ra" (Bereishis 8:21; Kidushin 30b). Excess talk also gives to the Yetzer opportunity to cling to his body.
R. Yonah: "U'Motze Ani Mar mi'Maves Es ha'Ishah" (Koheles 7:26) - death merely removes him from this world, but a woman will make his Nefesh perish forever. "Asher Hi Metzudim" (ibid.) - once one gazes at a woman, he is caught in her Metzudah (trap). Man sees his heart's desire, and does not see his end. A foolish dove in the Midbar sees the grain, but not the trap. "Va'Charamim Libah" (ibid.) - when she desires a man in her heart, he will stumble with her even if he does not desire her. His bad Mazal caused her to desire him. "Asurim Yadeha" (ibid.) - if she holds him in her hands, he is incarcerated; there is no solution for him. "Tov Lifnei ha'Elokim Yimalet Mimenah" (ibid.) - Hashem guards a Tzadik and does not summons for him something that he can stumble in it.
What is "me'Chelkas Lashon [Nochriyah]"?
Rashi: From the plastering over the eyes of a foreign language.
Malbim: "Eshes Ra" is a Jewish Zonah. Chelkas Lashon Nochriyah is a Nochris Zonah.
Malbim (according to Melitzah): They are ways of idolatry. [Torah guards from them], even though they are in ways of comparisons of Tevunah. "Lashon" always refers to Binah.
