Question
Why didn't Isaac just revert the blessing he had given to Yaakov under trickery and then bestow it back upon Esau?
Also, "And Esau said to Jacob, “Give me some of that red stuff to gulp down, for I am famished”—which is why he was named Edom. Im confused about this quote. Why is Esau chopping down Yaakovs stew mean his name is Edom?
Is the issue that I Am not understanding the definition of Edom?
Answer
In short, Isaac clearly suspects that it is Jacob who has come for the blessing: thus his feeling him, smelling him, and declaring suspiciously: "the voice is that of Jacob, but the hands are those of Esav". We must understand that his disagreement with Rebecca was whether it's easier for someone physical-oriented (Esav) to learn spirituality, or for someone spiritually-oriented (Jacob) to learn the ways of the physical world. Rebecca opted for Jacob while Isaac preferred Esav (25, 28), for the blessing is for the Land of Israel, which is both physical and spiritual. Isaac was scared that the studious Jacob, may neglect the Holy Land and leave it to weed. When Rebecca symbolically (!) and actually, dresses Esav's sleeves onto Jacob (all this in Breishit ch. 27), she is proving her point to Isaac (which is also the fulfillment of the prophecy which she knew (ch. 25, 22-23), but apparently Isaac didn't know). What clinches it, is when Isaac feels that Jacob can also be a man of the world, and do both- revealing the spirituality in the physical world, and even smells that Jacob has the "smell of the Field/Land which God has blessed him with", and only then did Isaac bless him. In other words, he now isn't worried about blessing Jacob. Afterwards, when Esav enters Isaac just pretends (!) to be surprised and frightened.
Regarding "Edom", there is a play-on-words here, for Esav was reddish from birth (either ruddy in skin color or a red-head, or both, for they often go together!), or in Hebrew: ADMN, and here he is gulping down the "red-red stuff" (in Hebrew ADM), thus his nickname: Edom (ADM). He also is a hunter and the entire picture is clearly of Esav is that he is a crude, wild (stereotype of red-heads, where it's extremely rare for the Bible to mention hair color!) physical-oriented glutton.
This is a good example, why it's so essential to learn Hebrew or to study with a Jewish rabbi who knows Hebrew, in order to understand the Bible properly.