All ye inhabitants— We have here the declaration made to the other people of the world to expect the fall of the Assyrian. God invites all the people of the earth to this sight; that as soon as they should observe the sign appointed by God, namely, the standards lifted up on the mountains of Judaea, and the sound of the trumpets of the hostile army preparing to besiege Jerusalem, they should attend to the execution of this divine judgment. When he lifteth up, seems undoubtedly to mean the commander of this great army, or Sennacherib. Vitringa.
Related Commentaries of Isaiah 18:3
Isaiah 18:3
3 All ye inhabitants of the world, and dwellers on the earth, see ye, when he lifteth up an ensign on the mountains; and when he bloweth a trumpet, hear ye.