# though its waters roar and rage
"though the waters of the sea roar and rage." The words "roar" and "rage" describe the violent movements of the sea during a strong storm.
# mountains tremble with their swelling
The phrase "their swelling" refers to the waters of the sea as they rise and crash against the mountains. Alternate translation: "the swelling waters cause the mountains to tremble" (See: [[rc://en/ta/man/translate/figs-explicit]])