Two brothers – Tol’dot
The Torah says (Gen. 25:22) vayitrotz’tzu habanim, “the sons struggled”; the sages derive the verb from rutz, “to run”, suggesting that when their mother passed a place of learning, Jacob tried to get out of the womb, and when she passed a place of idolatry, Esau tried to get out.
Once they were born, the two sons remained locked in combat. Isaac didn’t always realise how he was being manipulated by Esau. Esau would come to his father with complicated, minute halachic questions such as whether straw or salt had to be tithed. Esau rejoiced that his son was so apparently meticulous in his religious observance.
The truth, as Rashi tells us, is that Esau was ish yode’a tzayid, “a man who knew how to hunt” – in a metaphorical way, hunting in the sense of ensnaring his father with his apparent piety which was really mere pretence.
Rivkah, the wife of Isaac, knew what was going on and worked out an elaborate scheme to show Isaac how gullible he was.