What does Isaiah 19:2 mean?
Isaiah has begun his oracle against Egypt. He is describing the judgment which the Lord will bring on this sometimes-great nation. It is the true Lord God, not the false idol Baal, who is riding into Egypt on a swift cloud. The Lord's arrival will terrify both the people and their idols (Isaiah 19:1).The result of God's judgment will be the disintegration of Egypt into endless factions. The Lord is the one who will bring about this division. He will incite the people to fight each other. This will come to all levels of society, from individual people to the highest levels of government.
Historically, Egypt broke into a dozens of self-governing city-states for several centuries starting around 2200 BC. Then the nation fell into chaos again around 1785 BC. Many rulers attempted to unite the realm, but their attempts were often frustrated by the competing false gods worshipped in the various regions. The general belief for the realm was that anyone who would be king must be a god, of some kind, himself.
In this way, the Lord used the people idols against them to divide the nation in His judgment.