The river that lay between some strong city and the advancing enemy was its strongest fortification when the bridge of boats was taken away. One of the ancient cities to which I have referred is described by one of the prophets as being held as within the coils of a serpent, by which he means the various bendings and twistings of the Euphrates, which encompassed Babylon, and made it so hard to be conquered. The primitive city of Paris owed its safety in the wild old times when it was founded, to its being on an island. Venice has lived through many centuries, because it is girded about by its lagoons. England is what it is, largely because of 'the streak of silver sea.' So God's city has a broad moat all round it. The prophet goes on to explain the force of his bold figure in regard to the safety promised by it, when he says: 'Wherein shall go no galley with oars, neither shall gallant ship pass thereby.' Not a keel of the enemy shall dare to cut its waters, nor break their surface with the wet plash of invading oars. And so, if we will only knit ourselves with God by simple trust and continual communion, it is the plainest prose fact that nothing will harm us, and no foe will ever get near enough to us to shoot his arrows against us. That is a truth for faith, and not for sense. Many a man, truly compassed about by God, has to go through fiery trial and sorrow and affliction. But I venture to appeal to every heart that has known grief most acutely, protractedly, and frequently, and has borne it in the faith of God, and with submission to Him; and I know that they who are the 'experts,' and who alone have the right to speak with authority on the subject, will confirm the statement that I make, that sorrows recognised as sent from God are the truest blessings of our lives. No real evil befalls us, because, according to the old superstition that money bewitched was cleansed if it was handed across running water, our sorrows only reach us across the river that defends. Isaiah is full of symbols of various kinds for the impregnability of Zion. Sometimes, as in my text, he falls back upon the thought of the bright waters of the moat on which no enemy can venture to sail. Sometimes he draws his metaphor from the element opposed to water, and speaks of a wall of fire round about us. But the simple reality that lies below all the poetry is, that trust in God brings His presence around me, and that makes it impossible that any evil should befall me, and certain that whatever does befall me is His messenger, His loving messenger, for my good. If we believed that, and lived on the belief, the whole world would be different. III. Take, again, another aspect of this same thought, which suggests to us God's presence as our true refreshment and satisfaction.