Or HaChaim on Genesis 27:13/אור החיים על בראשית כ״ז:י״ג

1 עלי קללתך בני, "may your curse be on me my son!" The reason that she added the word "my son," although she had been talking to him all the time was that she referred only to what Jacob had said last. We have a rule in Makkot 11 that the curse of a Torah scholar, even if uttered only conditionally, is effective. Had Rebeccah not added the word "my son," we would have thought that she referred to Jacob's being cursed by Isaac when he found out he had been tricked.

2In order to understand Rebeccah's special love for Jacob the following considerations may help. Rebeccah generally was looked upon askance because she had given birth to the wicked Esau. We find in nature that parts of a whole display an affinity for other parts of the same whole. Rebeccah testified that this rule did not apply in her case, that her deeds proved that she had no affinity for Esau. Her womb was indeed blessed, and the good part (Jacob) represented that which was normal, hence her love for Jacob. The Torah teaches us this by repeatedly describing Jacob as Rebeccah's son even in instances where these additional words are otherwise quite superfluous (compare verses 6,8,11,13,15,17,42). All of this is to underline that Jacob's righteousness was a direct outgrowth of his righteous mother. The fact that she had given birth also to an Esau was not a reflection on his mother's personality.

3Kabbalists, of course, are aware that there are mystical dimensions which account for the emergence of Esau as a potentially wicked person, whereas it was Rebeccah's union with Isaac which was the cause of any pollutant disturbing her holiness. Rabbi Shimon ben Yochai is quoted in the Zohar (Sullam edition Chayey Sarah 251) as explaining that the reason the Torah describes Isaac as loving his wife Rebeccah, something that is natural and does not require special mention, is that the love of the male for the female is rooted in the "left" side of the emanations. in Isaac's case it was the fire of the גבורה, his predominant characteristic which stems from the "left side" of the emanations.. If the holiness of the two was tainted in any way this was due more to Isaac than to Rebeccah. Jacob's physical perfection is compared to that of Adam's before the sin, as we know from Baba Metzia 84. He did not therefore inherit any pollutant from his mother. Students of the Kabbalah will understand all this. [I have elaborated on the author's text to make it more intelligible for the non-kabbalist. Ed.] When we wrote earlier (25,20) that the reason that Esau was wicked was because Rebeccah had a wicked brother called Laban, this did not influence Rebeccah's character.