Isaiah 10:17

The light of Israel. To sin and sinners the divine glory is a consuming fire (see Ex. 24:17; Deut. 4:24; 9:3; Isa. 33:14; Heb. 12:29). The Holy One, whose brightness is the glory and joy of the redeemed, is as a flame that consumes briers and thorns. “Briers” and “thorns” are favorite figures of Isaiah in describing the ruinous work of sin (see on Isa. 9:18). Ezekiel (ch. 2:6) also uses this figurative expression for the wicked, and Paul (Heb. 6:8) likewise speaks of briers and thorns as the cursed fruitage of evil, “whose end is to be burned.”

In one day. These words point to some speedy and sudden destruction that would befall the Assyrians. Isaiah here looks forward to such scenes as the destruction of 185,000 men of Sennacherib’s army in one night (ch. 37:36).