And one people shall be stronger than the other (Gen. 25:23)
Rashi comments: When one rises, the other falls. Jacob and Esau symbolize the struggle between the G-dly soul and the animal soul, between a person's good and evil inclinations. When a Jew's G-dly soul is dominant and exerts itself, there is no need to combat the animal soul - it "falls" by itself. Light does not have to fight darkness to illuminate - as soon as it appears, the darkness vanishes. So too, does the light of holiness dispel all evil. (Sefer Hamaamarim)
Sojourn in this land, and I will be with you (Gen. 26:3)
The Torah uses the word "sojourn" instead of "dwell" to teach us that one must always consider oneself a temporary resident of this world. "The Shechina (G-dly presence) does not move away from one who considers himself a stranger in this world," we are taught. The second part of G-d's promise, "I will be with you," will be fulfilled when Jacob thinks of himself in this manner. (Vayechakem Shlomo)
And they departed from him in peace (Gen. 26:31)
Even after having partaken of a meal with the tzadik, Isaac, Avimelech still departed convinced of his own self-importance. This is something that a Jew would have been unable to do. A Jew, when in the presence of a tzadik, realizes his own shortcomings and is humbled. (Reb Bunim)
Reprinted from the Parashat Toldos 5763/2002 edition of L’Chaim