What does Genesis 25:28 mean?

Now fully-grown men, the personalities and preferences of Esau and Jacob have been established. Esau is a hunter, an outdoorsman, apparently a man of action. Jacob prefers to stay in the tents. He's a quiet person.

They bond with their parents accordingly. Isaac loves the manly son who brings home the game to eat. He's likely proud of the firstborn boy known as the great hunter. Rebekah, however, loves her quiet, stay-at-home second-born son. Those attachments will play an important role in what comes next. Upcoming passages will show that this "love" is hardly equally distributed; each parent clearly prefers one child over the other, and seemingly makes no secret of that fact. Parental favoritism leads to problems, a lesson Jacob seems to forget when he has children of his own (Genesis 37:1–4).

The twins' divergent personalities also come with drawbacks. Esau will prove to be somewhat reckless, even careless (Genesis 25:32). And Jacob is both manipulative and dishonest (Genesis 25:33). While Esau will certainly feel the consequences of his actions (Genesis 25:34), Jacob will later experience, first-hand, what it's like to be caught in a scam (Genesis 29).