Obadiah 1:10

Thy brother Jacob This was the great aggravation of the violence. "Thou shalt not abhor an Edomite, for he is thy brother," was the command of God to the Jews (Deuteronomy 23:7). Treachery from friends and allies was the meet punishment of such a sin.

thou shalt be cut off for ever As the sin of Edom is concisely expressed in this verse by the one word violence, the details of that violence being afterwards given, so the punishment of Edom is here proclaimed in its ultimate completeness, the steps of his total extinction being in like manner afterwards described.