For my sword shall be bathed in heaven,.... That is, the sword of the Lord, as it is called in the next verse Isa 34:6, and it is he that is speaking; it designs the vengeance of the Lord, the punishment he will inflict on the wicked, said to be "bathed in heaven", because determined and prepared there; the allusion may be to the bathing of swords in some sort of liquor, to harden or brighten them, and so fit them for use.
Kimchi renders it, "my sword" which is "in heaven shall be bathed", that is, in the blood of the slain; "heaven" may denote the whole Roman Papal jurisdiction, as it does the whole Roman Pagan empire in Re 12:7 and may design the principal men in it, those that are in the highest places and offices, in whom the sword of the Lord shall be first drenched, and be as it were satiated and inebriated with the blood of them:behold, it shall come down upon Idumea; with great weight, force, and vengeance, having a commission from heaven to execute.
Idumea is here particularly mentioned, because the Edomites were implacable enemies to the Jews, and so are here put for all the enemies of God's church and people, all the antichristian states, particularly Rome, which the Jews, as Jerom observes, understand by Edom or Idumea here:upon the people of my curse to judgment; a very descriptive character of the Papists, the people of God's curse, and righteously so; those who have anathematized his people, and cursed them with bell, book, and candle, are anathematized by him, devoted to destruction, and doomed to be accursed, sentenced to ruin, and on whom judgment shall pass, and shall be executed; they shall hear, "go, ye cursed", both here and hereafter, at the fall of Babylon, and at the general judgment.
The Targum is,"because my sword is revealed in heaven; behold, upon Edom it is revealed, and upon the people whom I have condemned to judgment.'