The sons of Eliphaz. The text says “Zephi,” with a yod; but in the Torah (Genesis 36:11) this appears as “Zepho,” with a vav.

Kenaz, Timna, and Amalek. From this verse it seems that Timna was a son of Eliphaz, but the Torah (Genesis 36:12) says that Timna was a concubine of Eliphaz and that she bore him Amalek! Some explain (cf. Rashi ibid.) that Timna is the mother of Amalek as it says in the Torah, and that she was misbegotten. For Eliphaz had relations with Seir’s wife, the mother of Lotan, and she bore him Timna—either during his lifetime or after his death—and Ezra made a subtle observation in the Torah that there is a paseq after “Timna,” so that the intent is: “Gatam, Kenaz, and Timna” (Genesis 36:11–12), meaning that she too was his daughter. Afterward, though, she became his concubine and bore him Amalek. It is for this reason, then, that the text says, “and Lotan’s sister was Timna” (Genesis 36:22, I Chr 1:39)—not “Seir’s daughter,” but rather “Lotan’s sister.” But this interpretation is midrashic: had Timna been the daughter of Eliphaz, the text would not have included her in the list of sons; for Scripture does not do this without saying so explicitly, as in: “and his daughter Dinah” (Genesis 46:15), and: “and their sister Serah” (Genesis 46:17). In my view the text adopts an abridged style: because Ezra did not need to be explicit, inasmuch as the matter is explicit in the Torah, he presented the genealogical lines in abridged form. He was similarly brief concerning the sons of Shem, recording Shem’s grandsons in the list of sons for the purpose of brevity, so that when the text says “Aram [and Uz and Hul]” (1 Chronicles 1:17) it is as though it says, “Aram’s sons were Uz and Hul.” Here too, then, he was brief in writing “Timna.” Indeed, he could have been even briefer and written “Zepho, Gatam, Kenaz, and Amalek”; but because Amalek was not equal to the other sons—for they were sons of wives whereas he was the son of a concubine—he separated them by mentioning his mother. And it was adequate for him just to write “Timna,” because the matter is laid out in the Torah.