וַיֵּ֥לֶךְ עֵשָׂ֖ו אֶל־יִשְׁמָעֵ֑אל וַיִּקַּ֡ח אֶֽת־מָחֲלַ֣ת ׀ בַּת־יִשְׁמָעֵ֨אל בֶּן־אַבְרָהָ֜ם אֲח֧וֹת נְבָי֛וֹת עַל־נָשָׁ֖יו ל֥וֹ לְאִשָּֽׁה׃ (ס)
so Esau went unto Ishmael, and took unto the wives that he had Mahalath the daughter of Ishmael Abraham’s son, the sister of Nebaioth, to be his wife.
Read kabbalistic (mystical) interpretation of Genesis 28:9: and classical mystical sources.