Genesis 28:6-9

"Now Esau saw that Isaac had blessed Jacob and sent him away to Paddan-aram; to take a wife from thence; and as he blessed him, he gave him charge, saying, Thou shalt not take a wife of the daughters of Canaan; and that Jacob obeyed his father and his mother, and was gone to Paddan-aram: and Esau saw that the daughters of Canaan pleased not Isaac his father; and Esau went unto Ishmael, and took, besides the wives that he had, Mahalath the daughter of Ishmael Abraham's son, the sister of Nebaioth, to be his wife."

One cannot resist the opinion that Esau was a shade late with what he must have considered some kind of a concession to the opinions of his parents. "This was a rather pathetic attempt, a closing of the barn door after the horse was gone."[3] It is true that this marriage bore a superficial resemblance to that of Jacob, in that Jacob married his mother's niece, and Esau married his father's niece. But the shocking difference lay in the fact that Esau married out of the covenant line, Ishmael also having been rejected as heir of the promises. Besides this, he already had two wives from the daughters of Canaan, and the only thing he did was to add another woman to his polygamous household. Alas, Jacob fell into the same error, but with provocation that did not exist in the case of Esau. The behavior of both these grandsons shows what a colossal mistake Abraham made when Hagar became a second wife.

These marriages by the patriarchs of wives closely akin to them were possible and permitted because, "The race was young enough that the danger of accumulated mutational defects was minimized."[4] Later, in the times of Moses, when genetic problems were more likely, the Law forbade the marriages of persons of near kinship.

Despite the failure of Esau to make any essential improvement in his situation by this additional marriage, one may sympathize with what he no doubt intended as a gesture of reconciliation.