This is the language of the appearance of God (theophany). When he appeared at Sinai, the whole mountain trembled violently (Exodus 19:18; see also Judges 5:4; Psalm 66:8). And that marked the beginning of a new era in the Lord’s dealings with his people. Now he foretells another appearing. Only now, it will not just be one mountain. Everything will be subject to this divine shaking. It won’t be an actual earthquake. Rather, once again, a new world order was coming, and the rebuilding of the temple was part of the preparations for that great change to come.1 The Lord will appear and do something worldwide.
6 For thus says the LORD of hosts: Yet once more, in a little while, I will shake the heavens and the earth and the sea and the dry land.