The total ruin of a once-great city leaves a lasting mark not only on its landscape but on the people who witness its fall. The destruction serves as a direct punishment because the inhabitants alienated and desecrated their own home [מלבי״ם].
In the aftermath of the severe blows and disasters that the city absorbed, anyone passing by the ruins will experience a profound emotional and physical response. The sheer scale of the desolation will leave onlookers completely stunned and filled with deep astonishment [מצודת דוד, מצודת ציון, ביאור שטיינזלץ]. This overwhelming shock will naturally trigger a physical reaction. People will instinctively purse their lips to whistle or hiss, which is a typical human response when standing before the tragic collapse of something that was once grand and important [מצודת ציון, ביאור שטיינזלץ].