What are the connotations of the words "Lo Sikach"?
Rashi: It implies that marrying the daughter or the mother is only forbidden if he actually married the first woman, but not if he raped (or seduced) her.
Who is included in "Ishah u'Bitah"?
Rashi: It incorporates her daughter - irrespective of whether she is from him or from another man (and his mother-in-law and her mother - Rashi in Yevamos, 2a).
Why here, does the Torah discuss Ishah u'Bitah, and in Kedoshim, 20:14, it reverses the order "Ishah ve'Imah"?
Oznayim la'Torah: Because we might otherwise have thought that it is forbidden to marry the daughter after the mother, since it is obviously a matter of desire to marry a younger woman, whereas to marry the mother after the daughter is permitted, since the son-in-law would perform a Mitzvah - to look after his elderly mother-in-law, and to sustain her.
What are the connotations of "Zimah Hi"?
Rashi #1: It means a plot that is hatched by the Yeitzer ha'Ra, to commit adultery. 1
Rashi #2 (in Yechezkel, 16:43): It means a plan - sometimes good and sometimes bad.
Ramban, Moshav Zekenim, Seforno and Targum Onkelos: It means 'a sinful plot'. 2
Targum Yonasan: 'It is adultery'.
Sanhedrin, 75a: It teaches us, via a Gezeirah Shavah "Zimah Hi" "Zimah" in Kedoshim, 20:14 that, just as there, in connection with the punishment - 'above' (a mother-in-law's mother) is the same as 'below'(a wife's daughter's daughter), so too here, does the warning by 'below' cover 'above'. 3 :
Kerisos, 15a: The word "HI" teahes us that if a man who is married to three women, has relations with the mother of one of them who is also the maternal grandmother of one of the others and the paternal grandmother of the third one, 4 is only Chayav one Chatas.
See Sifsei Chachamim.
Ramban and Moshav Zekenim: Whereas a plan to do good is called 'Mezimah'. And the Torah inserts it specifically here, because a man who marries a woman and her daughter or a woman and her mother, bearing in mind their close relationship and physical resemblance, he tends to be intimate with one of them and to think about the other. Consequently, the Torah demonstrates its disdain of the perpetrator by describing it as "Zimah"
And the Gemara makes the reverse D'rashah to learn above from below regarding the punishment from the warning.
See Torah Temimah, note 40.
