GEN638 Judaism believes that man is born with the desire to do evil, the evil impulse, as implied in the Torah [this verse] and receives the yetzer hatov, the impulse of good, only at the age of thirteen or twelve for a woman Avot DeRabbi Natan 16:2.  Therefore, if left alone, it would be very difficult for a person to overcome the evil desire.  One of the purposes of the Torah, the sole purpose, according to the Talmud Kiddushin 21b, was to teach man how to overcome and defeat his desire for evil.  God sets up all of human endeavor as a moral test for the human being.  He presents the moral situations, and it is up to us to react properly and defeat the desire to do bad… If we overcome desire and exercise self-control, then we will get reward, whether it be a slimmer figure when dieting or entrance to the world to come.  We can indeed view each act in our lives as a test.  Every morning, each adult decides whether to go to work or not.  At the breakfast table, we choose to be nice or not nice to our spouse.  On the road, we must decide to exceed or not to exceed the speed limit.  Children must decide each day whether or not to do homework.  AMEMEI 247-8