If you’re hoping for a simple and clear-cut answer from real theologians, you’re in for a disappointment.
According to traditional Jewish commentators, the set-up is like this: Esau is a class A jerk. Jacob is a nice guy, if a bit naive- in fact he’s a bit of a mama’s boy.
Esau sells his birthright- basically, the right to be Isaac’s primary heir- for a bowl of bean soup. This does not speak well for Esau’s commitment to the family cause. It also means that Jacob is now technically the firstborn, and the rightful recipient of Isaac’s blessing.
Problem is, Isaac has a blind spot when it comes to his actual older son. Daddy dotes on Esau, and refuses to believe he could do any wrong. Esau is also very careful not to misbehave when his father’s around.
So, Rebecca- who has a lot better insight into her sons’ natures than Isaac does- figures that if Jacob can’t get his blessing outright, he can disguise himself as Esau. If you look at the text (especially in the orignal Hebrew), Jacob is rather reluctant, but Rebecca gives him some goat skins and tells him not to worry.
This segues into the age-old question of whether the ends justify the means. As those of you familiar with the saying, “Three Jews, three opinions” can guess, the only consensus is that there is no consensus. Even the rabbis who say Jacob’s deception was ultimately justified admit that this is a very, very grey area.
You can’t really argue that Jacob went scot-free and lived happily ever after, either. Immediately after the birthright fiasco, he has to run away from an angry Esau. He spends twenty years in exile, living with a conniving sneak of an uncle (there’s a reason he felt the need to pull the tricks with the sheep). He ends up accidentally married to four women, only one of whom he really loves. She dies on the way back home. His daughter gets raped, his favorite son gets kidnapped and sold into slavery by his own brothers. No, his life wasn’t all fun and games.