Adam Clarke on Psalms 114:3

The sea saw it, and fled - Mr. Addison has properly observed (see Spect. No. 461) that the author of this Psalm designedly works for effect, in pointing out the miraculous driving back the Red Sea and the river Jordan, and the commotion of the hills and mountains, without mentioning any agent. At last, when the reader sees the sea rapidly retiring from the shore, Jordan retreating to its source, and the mountains and hills running away like a flock of affrighted sheep, that the passage of the Israelites might be every where uninterrupted; then the cause of all is suddenly introduced, and the presence of God in his grandeur solves every difficulty.