Charles H. Spurgeon on Psalms 18:9

Amid the terror of the storm Jehovah the Avenger descended, bending beneath his foot the arch of heaven. ""He bowed the heavens also, and came down." He came in haste, and spurned everything which impeded his rapidity. The thickest gloom concealed his splendour, "and darkness was under his feet;" he fought within the dense vapours, as a warrior in clouds of smoke and dust, and found out the hearts of his enemies with the sharp falchion of his vengeance. Darkness is no impediment to God; its densest gloom he makes his tent and secret pavilion. See how prayer moves earth and heaven, and raises storms to overthrow in a moment the foes of God's Israel. Things were bad for David before he prayed, but they were much worse for his foes so soon as the petition had gone up to heaven. A trustful heart, by enlisting the divine aid, turns the tables on its enemies. If I must have an enemy let him not be a man of prayer, or he will soon get the better of me by calling in his God into the quarrel.