Charles H. Spurgeon on Psalms 18:4

"The floods." There is no metaphor of more frequent occurrence with the sacred poets, than that which represents dreadful and unexpected calamities under the image of overwhelming waters. This image seems to have been especially familiar with the Hebrews, inasmuch as it was derived from the peculiar habit and nature of their own country. They had continually before their eyes the river Jordan, annually overflowing its banks, when at the approach of summer the snows of Libanus and the neighbouring mountains melted, and, suddenly pouring down in torrents, swelled the current of the river. Besides, the whole country of Palestine, although it was not watered by many perennial streams, was, from the mountainous character of the greater part of it, liable to numerous torrents, which precipitated themselves through the narrow valleys after the periodical rainy seasons. This image, therefore, however known and adopted by other poets, may be considered as particularly familiar, and as it were, domestic with the Hebrews; who accordingly introduced it with greater frequency and freedom. —Robert Lowth (Bishop), 1710-1787.