כז:יג | 27:13
ותאמר לו אמו עלי קללתך בני
And his mother said to him, “Let your curse be upon me, my son.”
When Rivkah heard about Yitzchak’s plan to bestow his great‑est blessings upon Eisav, their wicked son, she told Yaakov, the righteous son, to trick Yitzchak into giving him the blessings instead. But Yaakov was concerned that Yitzchak would catch on to his act, and that Yaakov would end up with curses in‑stead of blessings. Rivkah therefore guaranteed him that she took full responsibility, saying, “Let your curse be upon me, my son,” whereupon Yaakov agreed to go ahead with the plan.
Now, Yaakov was a devoted son, and was certainly as con‑cerned for his mother’s welfare as he was for his own. Clearly, then, his mother’s guarantee that any curse would transfer to her could not have been very convincing!
Rather, what persuaded Yaakov was Rivkah’s willingness to take such great risk in order for him to receive the blessings. Through her offer, Rivkah demonstrated that these blessings were worth any risk involved in receiving them. In fact, the risk‑taking itself would made Yaakov worthy of receiving them.
Rivkah understood that these blessings were so extraordi‑nary and unfathomable that they could not be earned through normal and rational means. She realized that to be the fertile soil in which these transcendent blessings could take root, one needed to be willing to transcend the security of his perfectly calculated and balanced lifestyle—he must be ready for me-siras nefesh, self‑sacrifice.
Through her readiness to take such great risks for Yaa‑kov to receive the blessings, Rivkah inspired within Yaakov an “uncalculated” readiness for mesiras nefesh, whereby he became worthy of blessings that surpass anything the mind could possibly grasp.
—Likkutei Sichos, vol. 1, p. 56