6. God himself will be their protector and Saviour, v. 21, 22. This the principal ground of their confidence: "He that is himself the glorious Lord will display his glory for us and be a glory to us, such as shall eclipse the rival-glory of the enemy." God, in being a gracious Lord, is a glorious Lord; for his goodness is his glory. God will be the Saviour of Jerusalem and her glorious Lord, (1.) As a guard against their adversaries abroad. He will be a place of broad rivers and streams. Jerusalem had no considerable river running by it, as most great cities have, nothing but the brook Kidron, and so wanted one of the best natural fortifications, as well as one of the greatest advantages for trade and commerce, and upon this account their enemies despised them and doubted not but to make an easy prey of them; but the presence and power of God are sufficient at any time to make up to us the deficiencies of the creature and of its strength and beauty. We have all in God, all we need or can desire. Many external advantages Jerusalem has not which other places have, but in God there is more than an equivalent. But, if there be broad rivers and streams about Jerusalem, may not these yield an easy access to the fleet of an invader? No; these are rivers and streams in which shall go no galley with oars, no man of war or gallant ship. If God himself be the river, it must needs be inaccessible to the enemy; they can neither find nor force their way by it. (2.) As a guide to their affairs at home: "For the Lord is our Judge, to whom we are accountable, to whose judgment we refer ourselves, by whose judgment we abide, and who therefore (we hope) will judge for us. He is our lawgiver; his word is a law to us, and to him every thought within us is brought into obedience. He is our King, to whom we pay homage and tribute, and an inviolable allegiance, and therefore he will save us." For, as protection draws allegiance, so allegiance may expect protection, and shall have it with God. By faith we take Christ for our prince and Saviour, and as such depend upon him and devote ourselves to him. Observe with what an air of triumph, and with what an emphasis laid upon the glorious name of God, they comfort themselves with this: Jehovah is our Judge, Jehovah is our Lawgiver, Jehovah is our King, who, being self-existent, is self-sufficient, and all-sufficient to us.