This very remarkable characterisation of God stands here as a kind of seal, set upon the preceding prophecy. It is the reason why that will certainly be fulfilled. And what precedes is mainly a promise of a deliverance for Israel, which was to be a destruction for Israel's enemies. It is put in very graphic and remarkable metaphors: 'Like as a lion roareth on his prey when a multitude of shepherds is called forth against him, he will not be afraid of their voice, nor abase himself for the noise of them: so shall the Lord of hosts come down to fight for Mount Zion.' The enemies of Israel are picturesquely and poetically represented as a crowd of shepherds vainly trying to scare a lion by their shouts. He stands undaunted, with his strong paw on his prey, and the boldest of them durst not venture to drag it from beneath his claws. So, says Isaiah, with singularly daring imagery, God will put all His strength into keeping fast hold of Israel, and no one can pluck His people from His hands. Then, with a sudden and striking change of metaphor, the prophet passes from a picture of the extreme of fierceness to one of the extreme of tenderness. 'As birds flying'--mother birds fluttering over their nests--'so will the Lord of hosts defend Jerusalem,' hovering over it and going from side to side to defend with His broad pinions, 'passing over, He will preserve it.' These figures are next translated into the plain promise of utter discomfiture and destruction, panic and flight as the portion of the enemies of Israel, and the whole has this broad seal set to it, that He who promises is 'the Lord, whose fire is in Zion, and His furnace in Jerusalem.' We shall not understand these great words if we regard them as only a revelation of destructive and terrible power. They are that indeed, but they are far more than that. It is the very beauty and completeness of this emblem that has a double aspect, and is no less rich in joy and blessing than pregnant with warning and terror. As Isaiah says in another place, Jerusalem is 'Ariel,' which probably means 'the hearth of God.' His presence in the city is as a fire for the comfort and defence of the happy inhabitants, and at the same time for the destruction of all evil and enemies. Far more truly than He dwelt in the city of David does God dwell in the Church, and His presence is its security. What, then, of instruction and hope may we gather from this wonderful emblem? I. In the Church, God is present as a great reservoir of fervid love.