ישעיהו, פרק י׳, פסוק י״ז

The downfall of the Assyrian army unfolds as a sudden and dramatic reversal. The very power that brings salvation to the Israelites instantly transforms into an instrument of destruction against their enemies. The primary approach among commentators is that God acts as a dual force in this event. He brings light to the Israelites, rescuing them from the darkness of their troubles, while simultaneously becoming a consuming fire against the Assyrian camp [רד״ק]. In practice, this divine judgment was carried out by an angel who struck down the enemy forces [אבן עזרא].

Alternatively, this light is understood symbolically as the merit of the Torah studied by King Hezekiah, which acted as a protective fire against Sennacherib, while the holiness refers either to God or to the righteous people of that generation [רש״י]. Another perspective sees a combination of two elements bringing about the rescue. The light represents the end of a harsh decree, much like morning light banishing the night, while the holiness reflects the pure actions of the Israelites. Thanks to these deeds, the rescue manifests as a massive flame. Unlike a regular fire, a towering flame is visible from a great distance, indicating a highly public and undeniable miracle [מלבי״ם].

This divine fire is destined to consume thorns and briers [מצודת ציון, שד״ל, ביאור שטיינזלץ]. These thorns serve as a metaphor for the Assyrian camp and its wicked members [אבן עזרא], particularly the officers and mighty warriors of Sennacherib [רש״י, רד״ק]. They are likened to thorns because they tormented and brought pain to the nations of the world, much like a sharp thorn that pierces the skin [מצודת דוד, רד״ק].

In this imagery, God acts as the fire and the Assyrian camp as a forest. The fire naturally catches the low thorns first before spreading to consume the tall, towering trees [שד״ל]. Ultimately, this entire devastation will occur in a single day, marking a defeat for the Assyrian army that is swift, sudden, and absolute [ביאור שטיינזלץ].