55 The style here is typical of Hebrew narrative; after the tension is resolved with the dialogue, the working out of it is recorded in a rapid sequence of verbs (“gave”; “ate”; “drank”; “got up”; “went out”). See also Gen 3:1–7 for another example.
56 So Esau despised his birthright. This clause, which concludes the episode, is a summary statement which reveals the underlying significance of Esau’s actions. “To despise” means to treat something as worthless or with contempt. Esau’s willingness to sell his birthright was evidence that he considered it to be unimportant.

In other versions

Then Jacob gave Esau bread and lentil stew, and he ate and drank and rose and went his way. Thus Esau despised his birthright.

Then Jacob gave Esau some bread and some lentil stew. He ate and drank, and then got up and left.

So Esau despised his birthright.

Then Jacob gave bread and lentil stew to Esau; he ate, drank, got up, and went away. So Esau despised his birthright.

Then Jacob gave Esau some bread and lentil stew. Esau ate the meal, then got up and left. He showed contempt for his rights as the firstborn.

Then Jacob gave Esau bread, and thick lentil stew, and he ate and drank. Then he got up and went away. So Esau despised his birthright.

Then Jacob gave Esau bread and pottage of lentiles; and he did eat and drink, and rose up, and went his way: thus Esau despised his birthright.

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