Isaiah 10:17,18

And the light of Israel shall be for a fire, and his Holy One for a flame: and it shall burn and devour his thorns and his briers in one day;

The light of Israel ... shall burn ... his thorns - the Assyrian's wicked host; carrying out the image in the end of Isaiah 10:16 Yahweh, who is a light to Israel, shall be the "fire" (Deuteronomy 4:24; Hebrews 12:29) that shall ignite the thorns (the Assyrians, like dry fuel, already prey to flame, Nahum 1:10).

Verse 18. And shall consume the glory of his forest. The common soldiers, the princes, officers, etc., all alike together, shall be consumed (note, Isaiah 9:18).

In one day - (Isaiah 37:36.)

And of his fruitful field - literally, Carmel, a rich mountain in the tribe of Asher. Figurative for Sennacherib's mighty army. Perhaps alluding to his own boasting words about to be uttered, Isaiah 37:24, "I will enter the forest of his Carmel."

Both soul and body - proverbial for utterly; the entire man is made up of soul and body.

They shall be as when a standard-bearer fainteth. - `they shall be as when a sick man (from a Syriac root) wastes away.' Compare "leanness," i:e., wasting destruction (Isaiah 10:16) (Maurer). Or, 'there shall be an entire dissipation, like a perfect melting (namely, of the Assyrian army) (Horsley). I prefer the English version [ noceec (H5264), from naacac (H5264), to lift up]. When the standard-bearer faints, the whole army is dissolved. So Mercer, Piscator, and Calvin.