For forty years the prophet had been preaching to the Jews his gospel, _God-with-us_; but they never awakened to the reality of the Divine presence till they saw it in the dispersion of the Assyrian army. Then God became real to them (ver. 14). The justice of God, preached so long by Isaiah, had always seemed something abstract. Now they saw how concrete it was. It was not only a doctrine: it was a fact. It was a fact that was a fire. Isaiah had often called it a fire; they thought this was rhetoric. But now they saw the actual burning--_the peoples as the burning of lime, as thorns cut down that are burned in the fire_. And when they felt the fire so near, each sinner of them awoke to the fact that he had something burnable in himself, something which could as little stand the fire as the Assyrians could. There was no difference in this fire outside and inside the walls. What it burned there it would burn here. Nay, was not Jerusalem the dwelling-place of God, and Ariel the very hearth and furnace of the fire which they saw consume the Assyrians? _Who_, they cried in their terror--_Who among us shall dwell with the devouring fire? Who among us shall dwell with everlasting burnings?_ We are familiar with Isaiah's fundamental God-with-us, and how it was spoken not for mercy only, but for judgement (chap. viii.). If _God-with-us_ meant love with us, salvation with us, it meant also holiness with us, judgement with us, the jealousy of God breathing upon what is impure, false and proud. Isaiah felt this so hotly, that his sense of it has broken out into some of the fieriest words in all prophecy. In his younger days he told the citizens not _to provoke the eyes of God's glory_, as if Heaven had fastened on their life two gleaming orbs, not only to pierce them with its vision, but to consume them with its wrath. Again, in the lowering cloud of calamity he had seen _lips of indignation, a tongue as a devouring fire_, and in the overflowing stream which finally issued from it the hot _breath of the Almighty_. These are unforgettable descriptions of the ceaseless activity of Divine righteousness in the life of man. They set our imaginations on fire with the prophet's burning belief in this. But they are excelled by another, more frequently used by Isaiah, wherein he likens the holiness of God to an universal and constant fire. To Isaiah life was so penetrated by the active justice of God, that he described it as bathed in fire, as blown through with fire. Righteousness was no mere doctrine to this prophet: it was the most real thing in history; it was the presence which pervaded and explained all phenomena. We shall understand the difference between Isaiah and his people if we have ever for our eyes' sake looked at a great conflagration through a coloured glass which allowed us to see the solid materials--stone, wood and iron--but prevented us from perceiving the flames and shimmering heat.