A false sense of security often leads to devastating consequences. The prophet addresses a nation boasting of an unbreakable defense pact, an agreement they believed would grant them complete immunity from impending disaster. This prophecy shatters their illusion, making it clear that all the protections and alliances they relied upon will collapse entirely when faced with reality.
The primary approach among commentators is that the people claimed to have forged a binding contract with the forces of death and the underworld to save themselves. In practical terms, this represents the political alliances they leaned on for survival, such as their treaties with Assyria and Egypt [מלבי״ם]. However, this perceived immunity will be completely wiped away and erased [רש״י, מצודת ציון, רד״ק, אבן עזרא, שד״ל, שטיינזלץ]. Alternatively, some interpret their supposed protection not as a contract, but as a physical border or boundary. In this view, the barrier the nation attempted to build between itself and destruction will simply fail to hold and ultimately collapse [מצודת ציון, מצודת דוד].
The nation arrogantly boasted that the approaching enemy strike and impending hardship would never reach them. The prophet completely overturns their claim, declaring that the disaster will undoubtedly sweep right through their midst [מצודת דוד, אברבנאל]. As a direct consequence of their misplaced trust [אבן עזרא], their ultimate fate will be one of total defeat. They will be trampled and crushed beneath the feet of the invading Assyrian army as it marches through the land of Judah [מלבי״ם, מצודת ציון, שטיינזלץ].