Esau had been ill-treated and cheated by Jacob most of his life.  Jacob cheated him out of his birthright and his blessing.  Esau was so angry that he threatened to kill him after his father died.  The two brothers lived apart and were alienated from youth to adulthood.  When the day finally came that Esau could carry out his threat to kill his brother, and he had an army to do so, he relented and forgave.  He forgot about having justice, vengeance and retaliation and fell in the arms of his brother with a weeping embrace.  On that day he was free from that old bitterness that had crippled his soul.  He stumbled onto Christlikeness. 

“And Jacob lifted up his eyes, and looked, and, behold, Esau came, and with him four hundred men. And he divided the children unto Leah, and unto Rachel, and unto the two handmaids. And he put the handmaids and their children foremost, and Leah and her children after, and Rachel and Joseph hindermost. And he passed over before them, and bowed himself to the ground seven times, until he came near to his brother. And Esau ran to meet him, and embraced him, and fell on his neck, and kissed him: and they wept.” Genesis 33:1-4 (KJV)