Ps 103:8

“"The mountains ascend, and the plains go down, into the place which You have founded for them" [Psalm 104:8]. He is still speaking of waters. Let us not here understand mountains as of earth; nor plains, as of earth: but waves so great that they may be compared to mountains. The sea did sometime toss, and its waves were as mountains, which could cover those mountains the Apostles. But how long do the mountains ascend and the plains go down? They raged, and they are appeased. When they raged they were mountains: now they are appeased they have become plains: for He has founded a place for them. There is a certain channel, as it were a deep place, into which all those lately raging hearts of mortals have retired....They were mountains formerly, now they are plains: yet, my brethren, even a dead calm is sea. For wherefore are they not now violent? Wherefore do they not rage? Wherefore do they not try, if they cannot overthrow our earth, at least to cover it? Wherefore not?”