What does Isaiah 19:1 mean?
This section of the book of Isaiah contains a series of oracles against the nations in the region surrounding Judah. The oracle in chapter 19 focuses on the coming judgment of Egypt. Israel shared a long history with Egypt, dating all the way back to the time of the original patriarch Abraham (Genesis 12:10; 37:25–27; 50:22–24). That history also included several centuries of slavery and oppression (Exodus 1:8–14; 12:41).The Assyrian war machine was a looming threat to the region. So, some in Judah wanted to make an alliance with the powerful nation of Egypt against the Assyrians. Isaiah's oracle showed that Egypt had as much to fear from the Lord, and from the Assyrians, as any of the other nations in the region.
The oracle begins by picturing the Lord riding on a swift cloud in the sky, as if in a flying chariot. This was a common description of the god Baal during this era. Why would Isaiah use the same picture of the Lord God of Israel that was often used for Baal? It was an intentional displacement of Baal. Some commentators even interpret this as a form of mocking or sarcasm. In addition, it declares that the Lord was the true "god of the sky." Unlike Baal, the Lord could truly provide both rain and fertility to any people He chose.
In this case, the Lord will ride a cloud into Egypt for the purpose of judgment and destruction. Isaiah describes the idols of Egypt as trembling before the Lord's arrival. Isaiah uses humor to show the absurdity of worshipping false idols. If they weren't unliving, manmade hunks of wood, they would indeed tremble in fear in the presence of the one true God of heaven. They would remember how thoroughly the Lord had decimated Egypt through the plagues so many ages ago (Exodus 3:20).
It's not just the idols that tremble. Isaiah states that the hearts of the people of Egypt will wither within them when the Lord comes. Either His judgment or merely anticipating it will inspire fear. The courage of the Egyptians will dissipate in response to the Lord of Israel.