Parashas Toldos · Passuk 26:35
They were a source of bitterness to Yitzchak and Rivkah.
Rashi on Bereishis 26:35 (classical source on this passuk; not listed as a numbered Torah Temimah unit here).
Lemma / focus: מרת רוח.
English: Language of embittering the spirit—as in “you have been rebellious”; all their deeds were to provoke and cause grief. To Yitzchak and Rivkah—for they practiced idolatry.
Derash on the verse (Rashi) — not a formal named middah of the 13: “bitterness of spirit” is fixed as provocation, including idolatry.
Esav’s Hittite wives were a bitterness of spirit to Yitzchak and Rivkah; their deeds provoked and grieved, including idolatry.