The prophecy of destruction against Moab relies on the harsh, graphic imagery of a drunkard wallowing in his own filth to illustrate the severe humiliation awaiting the nation. For years, Moab remained untouched by the devastating wars that ruined the neighboring kingdoms of Israel and Judah. This unbroken peace gave them a deep sense of satisfaction and a false security in their own way of life [ביאור שטיינזלץ]. Swelling with pride, they spoke with contempt against God. They cruelly mocked the Israelites in their distress and arrogantly claimed that God lacked the power to save His own people from their enemies [רד״ק, מצודת דוד, חומת אנך].
As a consequence of this arrogance, Moab's enemies are called upon to force them to drink a cup of wrath and poison. This bitter draft will plunge the nation into absolute confusion and a total loss of their senses, much like a stumbling drunkard [רש״י, רד״ק, מצודת דוד]. This complete loss of reason serves as a direct, measure-for-measure punishment for the evil and calculating thoughts Moab harbored in their hearts against the Israelites [חומת אנך].
The punishment intensifies with the depiction of Moab thrashing in their own vomit. The primary approach among commentators understands this as a direct continuation of the drunkard metaphor. Just as an intoxicated person falls to the ground, rolling and hurting himself in his own sickness, Moab will suffer and face absolute ruin amidst the overwhelming troubles that will surround them [רד״ק, מצודת דוד, ביאור שטיינזלץ].
A unique perspective, however, reads this moment as one of profound delusion. In this view, the drunkard vomits the wine but becomes so disoriented that he mistakes the sickness for fresh wine and consumes it again. On a historical level, this sickness symbolizes a nation being expelled from its home. Moab will be exiled, secretly sneak back into their territory, and then be violently expelled a second time—as if the land vomits them out, swallows them back, and violently rejects them once more [מלבי״ם].
Ultimately, this process will reduce Moab to a public laughingstock, perfectly illustrating the principle of divine justice. When the Israelites were exiled to Babylon, and later when refugees tried to sneak back into their homeland like thieves, Moab stood by and cruelly laughed. Now, the tables will turn. Moab itself will be trampled and become an object of mockery in the eyes of all the nations.