When a nation falls, the reaction of its neighbors reveals their true character. The prophet delivers a sharp rebuke to those who arrogantly celebrated the destruction of the Israelites, turning a tragic downfall into a source of constant, cruel amusement. The enemies are challenged with a piercing rhetorical question about their relentless mockery. Because they chose to make the Israelites a laughingstock, they are destined to suffer the exact same fate and become a laughingstock themselves [רד״ק].
The prophet questions the nature of this intense ridicule, asking if the Israelites were caught like a band of common thieves. While it is typical for crowds to shout and jeer at a captured criminal, the Israelites were not in such a position. Nevertheless, they were subjected to the exact same humiliating treatment and malicious joy [רד״ק, מצודת דוד, ביאור שטיינזלץ].
Every time these enemies spoke of the Israelites, their words were filled with derogatory insults [מלבי״ם]. This verbal abuse was paired with a dramatic physical reaction. The primary approach among commentators is that this was a physical display of mockery. Whenever they discussed the exile of the Israelites, they would shake their heads in pure contempt [רש״י, מצודת דוד]. They danced, moved with malicious joy, and even lost their balance from laughing so hard at the tragedy [רד״ק, מלבי״ם, ביאור שטיינזלץ]. Alternatively, this shaking is understood not as their physical mockery, but as their ultimate punishment. Because they joyfully celebrated the ruin of the Israelites, they will face a mirrored consequence: they themselves will be violently shaken and forced to wander in exile [רש״י].