The sermon centers on Isaiah's prophecy concerning Cush (Nubia), a distant and powerful nation that, despite its strength and diplomatic reach, is ultimately subject to God's sovereign will. Through vivid imagery of buzzing wings and distant ambassadors, the text reveals that even the most formidable nations—like Egypt and Cush—are temporary and will be judged if they rely on human alliances rather than God. The central message is that God's promises endure, and His judgment is certain, yet He also announces a glorious gospel hope: nations, even those as far off as Cush, will one day bring offerings to Mount Zion, worshiping the Lord of Hosts. This vision of global redemption, rooted in Scripture and fulfilled in the New Testament—particularly in the Ethiopian eunuch's conversion—affirms that God's salvation extends to every tongue, tribe, and nation, demonstrating His faithfulness and sovereign grace.