????? ??? ??-????, ??????? ?? ??-???? ???? ???–?? ???, ????; ??-?? ???-???, ????
The Meforshim ask, why is it only now, after Eisav asks to eat “from the red stuff” is he given the name, or title, Edom? Certainly he could very well have been called this from birth, where we are 1st told that he is a redhead.
The Midrash teaches us that Shmuel HaNavi was afraid when he 1st met Dovid (HaMelech). He did not want him to be king since he was a redhead, since it is a sign of one who is a ???? ????, a murderer.
Hashem tells Shmuel that Dovid is Kosher, and the signs that Shmuels sees about murder refer to actions done correctly and through Beis Din.
So lets apply that here. Once Eisav is born, we see that he has a pull towards being a rasha and a murderer, on the other hand, he can easily use his kochos for good and be a Tzaddik Gamor, like Dovid Hamelech. For this reason, he wasnt called Edom initially, rather Eisav, from the loshon ????, which apparently has nice implications.
However, once Eisav comes back from the field and acts the way he does for some food. Now we see which way he is going, now we see that he isn’t interested in using his kochos for the good like Dovid Hamelech. Now that we know that his kochos will be used for evil he will be referred to him as Edom, the name indicating blood and murder.
(R’ Shaul Katzenelbogen, from Vilna)