'A rock, a fortress-house.' Now, what is the force of that metaphor? Stable being, as it seems to me, is the first thought in it, for there is nothing that is more absolutely the type of unchangeableness and steadfast continuance. The great cliffs rise up, and the river glides at their base--it is a type of mutability, and of the fleeting generations of men, who are as the drops and ripples in its course--it eddies round the foot of the rocks to which the old man looks up, and sees the same dints and streaks and fissures in it that he saw when he was a child. The river runs onwards, the trees that root themselves in the clefts of the rock bear their spring foliage, and drop their leaves like the generations of men, and the Rock is 'the same yesterday, and to-day, and for ever.' And God the Unchangeable rises, if I may so say, like some majestic cliff, round the foot of which rolls for ever the tide of human life, and round which are littered the successive layers of the leaves of many summers. Then besides this stable being, and the consequences of it, is the other thought which is attached to the emblem in a hundred places in Scripture, and that is defence. 'His place of defence shall be the munitions of rocks.' When the floods are out, and all the plain is being dissolved into mud, the dwellers on it fly to the cliffs. When the enemy's banners appear on the horizon, and the open country is being harried and burned, the peasants hurry to the defence of the hills, and, sheltered there, are safe. And so for us this Name assures us that in Him, whatever floods may sweep across the low levels, and whatever foes may storm over the open land and the unwalled villages, there is always the fortress up in the hills, and thither no flood can rise, and there no enemy can come. A defence and a sure abode is his who dwells in God, and thus folds over himself the warm wings that stretch on either side, and shelter him from all assault. 'Lead me to the Rock that is higher than I.' But the Rock is a defence in another way. If a hard-pressed fugitive is brought to a stand and can set his back against a rock, he can front his assailants, secure that no unseen foe shall creep up behind and deal a stealthy stab and that he will not be surrounded unawares. 'The God of Israel shall be your rearward,' and he who has 'made the Most High his habitation' is sheltered from 'the pestilence that walketh in darkness,' as well as from 'the destruction that wasteth at noon-day,' and will be cleansed from 'secret faults' if he keeps up unbroken his union with God, for the 'faults' which are not recognised as faults by his partially illuminated conscience are known to God. But the Rock is a defence in yet another way, for it is a sure foundation for our lives. Whoso builds on God need fear no change. When the floods rise, and the winds blow, and the rain storms down, the house that is on the Rock will stand.