Why does Esau hate Jacob? First, we should ask: Why does Esau exist? Why is there evil in our world? Why is there hatred and darkness? What could be wrong with a world made only of goodness, love, and light? In Genesis 33:4, the Torah tells us about a kiss: after thirty-four years of Jacob fleeing his brother's wrath, and after Esau never stopped wanting to kill him, Esau has a change of heart. When he sees Jacob approaching, he runs to him, embraces him, and kisses him.
But the word vaishakehu, The phrase "and he kissed him" has a dotted line over the word, which is the Torah's way of telling us that this was not a normal kiss. What was so abnormal about this kiss? Well, the Midrash cites two interpretations. One is that the Torah is telling us that it wasn't a real kiss—Esau was actually trying to kill Jacob by biting his neck. The other interpretation is that Esau kissed Jacob with all his heart; that's what was abnormal about the kiss, since "we know from the Torah that Esau hated Jacob.""
However you look at it, the truth is that Esau hates Jacob. No matter what Jacob does, Esau hates him. If Jacob tries to appease him, gives him gifts, acts like a brother would, Esau hates him even more. Why?
Evil exists because it is so much more powerful than good. Is there anyone in this world who loves with the same intensity as someone who hates? Is there a light as bright as the deepest darkness? Has there ever been an act of kindness performed with the same force and vigor as an act of cruelty?
That is why, the Kabbalists say, God created evil. Darkness exists so that it can be transformed into light, resulting in a luminance infinitely greater than light itself could create. Cruelty is implanted in the human heart so that we can harness its intensity and create acts of kindness infinitely more powerful than kindness itself could produce. Evil exists to be exploited by goodness.
Eissav's soul knows this—that he exists only to serve his younger brother. No matter how fiercely Eissav resists this truth, this ferocity will ultimately be Jacob's.
That is why Eissav hates Jacob so much: because he knows that his hatred is not his own.
By Yanki Tauber, extracted from www.jabad.org.ar