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.
All ye inhabitants of the world ... see ye ... hear ye - rather, ye shall see-shall hear. Call to the whole earth to be witnesses of what Yahweh ("He") is about to do.
When he lifteth up an ensign on the mountains. He will 'lift up an ensign,' calling the Assyrian motley hosts together (Isaiah 5:26) on "the mountains" round Jerusalem, to their own destruction. The antitype shall be the gathering of Antichrist's hosts against Jerusalem to their destruction (Zechariah 12:2-3; Zechariah 12:6; Zechariah 14:2-4). This (Isaiah 18:1-7) declares the coming overthrow of those armies whose presence is announced in Isaiah 17:12-13. The same motive which led Hezekiah to seek aid from Egypt led him to accept gladly the Ethiopian Tirhakah's aid (Isaiah 36:6; Isaiah 37:9). Ethiopia, Egypt, and Judea were probably leagued together against the common enemy, 713 BC See notes on Isaiah 22:1-25, where a difference of tone (as referring to a different period) as to Ethiopia is observable. Horsley takes the "ensign" to be the cross, and the "trumpet" the Gospel trumpet, which shall be sounded more loudly in the last days (Revelation 14:6-7).