ישעיהו, פרק כ״א, פסוק ד׳

A sudden, violent transition from the peak of joy and victory to the depths of terror and death forms the dramatic core of the prophet's message. Speaking in the voice of a doomed ruler, the narrative captures the final hours of Belshazzar, the King of Babylon. The primary approach among commentators is that this focuses on his famous, massive feast. It was a highly anticipated night that the king deeply desired and loved [רש״י, שד״ל, ביאור שטיינזלץ]. He threw this grand celebration to mark his army's victory over the Persian forces, arrogantly drinking from the sacred vessels stolen from the Temple in Jerusalem [רש״י, רד״ק, אבן עזרא, חומת אנך].

However, the celebration is abruptly shattered. God transforms this night of revelry into an experience of paralyzing terror [רד״ק, מצודת דוד], though some describe this simply as a sudden, tragic reversal of reality [שד״ל]. The panic strikes the moment the king sees a mysterious hand writing on the palace wall. This supernatural event signals an impending disaster: the sudden attack of the enemy, the immediate conquest of Babylon, and the king's own death that very night [רש״י, רד״ק, ביאור שטיינזלץ].

Faced with this doom, the king suffers a complete mental and physical collapse. He loses his senses, overwhelmed by a sorrow so deep that his mind unravels, leaving him feeling like a man hopelessly wandering off a path [מצודת דוד, מצודת ציון, ביאור שטיינזלץ]. This mental confusion rapidly devolves into severe physical anxiety. He is gripped by a tremendous panic, his body shaking violently and his knees knocking together in fright [רש״י, רד״ק, מצודת ציון]. This reaction goes far beyond ordinary fear; it is a total physical breakdown, a trembling of the tendons where his very life force seems to drain away [מלבי״ם]. Adding another layer to his fright, one perspective suggests that his terror is also tied to the frightening, monstrous idols of the invading Persians [אבן עזרא].

While the tragedy is largely viewed as the ruin of a night the king eagerly awaited, another approach suggests the focus is entirely on his internal state. The sudden shift represents the violent uprooting of his passions; in a single moment, all of his lust and desire are entirely stripped away and vanish [מלבי״ם]. The sheer sharpness of this transition—from the absolute height of joy to the horrific reality of slaughter—doubles his madness. Torn between the celebration he was just enjoying and the sudden doom crashing down upon him, the king's mind is plunged into the deepest abyss of panic [מלבי״ם].