The prophecy of destruction against Moab paints a dramatic picture of flight and sheer despair. The people are trapped between a mass slaughter in the valleys and a desperate, tear-filled escape toward the mountains. This vision of doom closely mirrors a parallel prophecy found in the book of Isaiah, with only minor changes in the wording [רד"ק].
Seeking shelter and a chance at survival, the Moabites attempt to flee to a high, mountainous area known as the ascent of Luchit [רש"י, מצודת דוד, רד"ק]. As they climb the mountain to find refuge, their grief is overwhelming. The intensity of their mourning is profound [רד"ק], and as they make their way up the steep path, they continually raise their voices, adding tears upon tears [מצודת דוד, מלבי"ם].
This panicked retreat to the mountains is driven by the horrors unfolding below in the descent of Choronayim, a low-lying valley region [מצודת ציון, מצודת דוד]. Historically, there were actually two places bearing this name, an upper and a lower location [רד"ק]. Down in this valley, the people face terrible devastation. The primary approach among commentators is that hostile enemies are actively attacking and causing massive destruction [מצודת ציון, רד"ק], while an alternative perspective suggests the text refers more broadly to the severe troubles overwhelming the people [מלבי"ם].
As the killing continues in the valley, a bitter cry of destruction echoes upward. It is the sound of this very slaughter that drives the terrified survivors to flee up the mountain in tears [מצודת דוד, ביאור שטיינזלץ].