When Esau was forty years old, he took Judith the daughter of Beeri the Hittite to be his wife, and Basemath the daughter of Elon the Hittite, and they made life bitter for Isaac and Rebekah.
Genesis 26:34-35

The names of Esau's two Canaanite wives (Yudit, meaning "praised", and Basmat, meaning "aromatic spice") indicate they might have been great women, but they were still Canaanites, a compromise with paganism, and completely unacceptable to God and Rebekah. Isaac renewed the metaphorical wells of his father by marrying a daughter of Terah, while Esau stopped them up by marrying daughters of Canaan.