בראשית, פרק ל״ו, פסוק ה׳

The expansion of Esau’s family reaches a turning point just before his departure from his homeland. The final record of his children focuses on the offspring of his wife Oholibamah. According to [הטור הארוך], she was a later addition to his household. Esau married her after his initial wives passed away without having children, a consequence of the deep grief those first wives had caused his parents, Isaac and Rebekah.

Among the children raised by Oholibamah, the figure of Korach stands out due to a dark family secret. The primary approach among commentators suggests that Korach was not actually Esau’s biological child. Instead, he was the product of an incestuous relationship between Esau’s son, Eliphaz, and Oholibamah, his father's wife.

This hidden lineage comes to light through a careful look at the family records. Initially, Korach is entirely absent from the list of Eliphaz’s sons. However, he abruptly appears later among the tribal chiefs descending from Eliphaz. This shift reveals that while Korach was raised as Oholibamah’s son, his true biological lineage traced back to Eliphaz. Commentators attribute this severe moral failure to Eliphaz rather than Esau because other accounts already point to Eliphaz's flawed character, making him the likely culprit for such an act.

The family record ultimately emphasizes the location of these births. All of these sons were born during the period when Esau still resided in the land of Canaan, establishing his family's presence there before he eventually uprooted his household and moved away [ביאור שטיינזלץ].