By emptying shall the earth be emptied. He confirms what he had already said, and declares that those changes will not be accidental, but that they are the work of God. In the first verse, he had expressly stated that God is making preparations for emptying the earth: he now asserts that it will happen, and adds the reason, that God hath purposed and determined to do it.

The land - Hebrew, 'The earth,' as in Isaiah 24:1. It is here rendered correctly 'the land,' as it should have been there - meaning the land of Canaan.
And spoiled - Its valuable possessions shall become the prey of the invading foe. This is an emphatic repetition of the declaration in Isaiah 24:1, to show the absolute certainty of that which was threatened.

The land shall be utterly emptied, and utterly spoiled,.... Entirely emptied of its inhabitants, and wholly spoiled of its riches and substance; this is repeated, and with greater strength, to confirm what is before said, and which receives a greater confirmation by what follows:
for the Lord hath spoken this word; who is able to perform it, and who is faithful to his threatenings, as to his promises; not a word of his shall ever fail; the judgments threatened to the antichristian world are his true and faithful sayings; and the ruin of Rome is certain, because strong is the Lord that judgeth her, Revelation 18:8.