Is Tzfi the same as Tzfo (Bereishis 36:11)?
Radak: Yes, just here his name is written with a Yud.
Who is Timna?
Radak #1, Malbim citing Rashi: Here it implies that he is Ben Elifaz. The Torah says that she was a Pilegesh to Elifaz and gave birth to Amalek. Some say that she was Amalek's mother, like the Torah says, and she was a Mamzeres 1 . Elifaz had Bi'ah with Se'ir's wife, the mother of Lotan, and gave birth to Timna, in Se'ir's life or after his death. Ezra was meticulous - another Torah verse says that she was [Elifaz'] daughter, and later his Pilegesh. Therefore, it says "v'Achos Lotan Timna 2 ."
Radak #2: The generations are written concisely, the grandson with the son, just like Utz v'Chul are listed [among Bnei Shem] with their father Aram (17). It should have said v'Gatam Kenaz va'Amalek. However, to teach that Amalek was not Ben Ishah like the others, rather, a Ben Pilegesh, it mentions his mother before him. This sufficed, for the Torah already said [that she was Elifaz' Pilegesh].
Peninim mi'Shulchan ha'Vilna Gaon (Bereishis 36:7), ha'Emek Davar (ibid. 16): Elifaz had a son Timna, and a concubine Timna. He changed his son's name to Korach.
Malbim: The Rashbam (Bereishis 36:12) said that Timna is read both above (among Bnei Elifaz - he had a son Timna) and below (a female was Elifaz' Pilegesh). The Vilna Gaon brought examples of this. Why is he not listed among Alufei Elifaz?! Also, why is Korach listed among Alufei Elifaz, but not among Elifaz' sons? Rather, Korach is Elifaz' son Timna from Esav's wife Ahalavimah. Therefore, he is listed both among Bnei Ahalavimah and among Alufei Elifaz. His mother called him Korach, and Elifaz called him Timna, like his Pilegesh. He is not listed explicitly among Bnei Elifaz, for when he was born, he was assumed to be Ben Esav. However, the word Timna can be read with the previous verse, like Rashbam says, to hint that he was Ben Elifaz. He is listed among Alufei Elifaz via the name Korach - by then it was known that he is Ben Elifaz 3 . Ezra taught this, via listing him among Bnei Elifaz.
There is no Isur of Mamzerus among Goyim, but there is a spiritual blemish. (PF)
Radak: This Perush is based on Derush. It is wrong. If Timna was Elifaz' daughter, she would not be listed among sons, without specifying, e.g. "v'Es Dinah Bito", "v'Serach Achosam." Malbim - it is fine to list a daughter among sons (since another verse proves that she was a female - PF).
How did this become known? Even if they knew that he was not from Esav (Esav was not intimate with her in the months preceding her pregnancy, or he had lost the ability to father children), and Elifaz and Aholivamah admitted to the adultery, perhaps she had Zenus also with others! Perhaps Korach looked exactly like Elifaz (refer to Bereishis 25:19:2:2, Devarim 32:18:1:4). (PF)
