Genesis 27:41-42

41So Esau hated Jacob because of the blessing with which his father blessed him, and Esau said in his heart, “The days of mourning for my father are at hand; then I will kill my brother Jacob.”

42And the words of Esau her older son were told to Rebekah. So she sent and called Jacob her younger son, and said to him, “Surely your brother Esau comforts himself concerning you by intending to kill you.