Things aren't always as they appear. Esau, a rugged man, a hunter, and a provider was well loved by his father, Isaac. Jacob was more of a momma's boy and stayed in the tent all the time. Kind of like the difference between a city boy and country boy. Esau, after coming in from the field, was exhausted and hungry. Jacob, being an opportunist and knowing how hungry he was, offered him some of the stew he was cooking if he would give up his birthright. Esau found no use for his birthright and gave it up for a moment of hunger. Esau allowed his hunger to rule over him and thus gave up his position in the family because of it. Jacob was now in line to become the patriarch. This is an example of brains over brawn. It appeared that Esau strength would make a good leader, but that was proved to be wrong. The choices we make are very important for our future. Make wise decisions, even in a moment of weakness.
This story is in Genesis 25:29-34
As obedient children, do not be conformed to the passions of your former ignorance, but as he who called you is holy, you also be holy in all your conduct, since it is written, "You shall be holy, for I am holy." 1 Peter 1:14-16