The People of the Book said Esau threatened to kill his brother when their father was dead. They also said that he asked his father to pray for him that Allah make the earth good for his offspring and multiply his sustenance and fruits.
When their mother knew that Esau threatened his brother Jacob, she commanded her son Jacob to go to her brother Laban in the land of Haran and abide with him for a time until his brother's anger had abated, and to marry one of the Laban's daughters. She told her husband Isaac to command him with that advice and pray for him, and he did.