Obadiah 1:10

The Prophet here sets forth the reason why God would deal so severely and dreadfully with the Idumeans. Had he simply prophesied of their destruction, it would have been an important matter; for the Jews might have thereby known that their ruin was not chance, but the scourge of God; they might have known that they themselves were with others chastised by God, and this would have been a useful instruction to them: but what brought them the chief consolation was to hear, that they were so dear to God that he would undertake the defense of their wrongs and avenge them, that he would have a regard for their safety. Hence, when they heard that God, because he loved them, would punish the Idumeans, it was doubtless an invaluable comfort to them in their calamities. To this subject the Prophet now comes.

For the unjust oppression of thy brother Jacob, etc. The word חמס chemes, violence, is to be taken passively; as though he said, “See, how thou hast acted towards thy brother Jacob.” And he calls him his brother, not for honor’s sake, but, on the contrary, for the purpose of showing forth more fully the cruelty of the Idumeans; for consanguinity had had no effect in preventing them from raging against their own brethren, and as it were against their own bowels. It was therefore a proof of barbarous inhumanity, that the Idumeans, forgetting their common nature, had been so inflamed with hatred against their own brethren: for, as it is well known, they had descended from the same common father, Abraham, and also from Isaac, and had the symbol of circumcision. The Idumeans indeed professed that they were the descendants of Abraham, and were God’s peculiar people. Since then God had made his covenant with their common father Isaac, and since they had equally retained circumcision, which was the seal of that covenant, how did it happen, that the Idumeans conducted themselves so cruelly towards their brethren? We hence see, that the name of brother in this clause — for the oppression of thy brother Jacob, is mentioned for the purpose of enhancing their crime.

As then, he says, thou hast been so violent against thy brother, cover thee shall reproach, and forever shalt thou be cut off. He intimates that the calamity would not be only for a time as in the case of Israel, but that the Lord would execute such a punishment as would prove that the Idumeans were aliens to him; for God in chastising his Church ever observes certain limits, as he never forgets his covenant. He proves indeed that the Idumeans were not his people, however much they might falsely boast that they were the children of Abraham, and make claim to the sign of circumcision; for they were professedly enemies, and had entirely departed from all godliness: it was then no wonder that their circumcision, which they had impiously profaned, was made no account of. But he afterwards more fully and largely unfolds the same thing.