48 Heb “The earth will quake when at the sound of their downfall.” However, as in many other places “earth” stands here metonymically for the inhabitants or people of the earth (see E. W. Bullinger, Figures of Speech, , and compare usage in 2 Sam 15:23; Ps 66:4).
49 Heb “the Red Sea,” of which the Gulf of Aqaba formed the northeastern arm. The land of Edom once reached this far according to 1 Kgs 9:26.

In other versions

At the sound of their fall the earth shall tremble; the sound of their cry shall be heard at the Red Sea.

At the sound of their fall the earth will tremble;

their cry will resound to the Red Sea.

At the sound of their fall the earth will quake; the sound of her cry will be heard at the Red Sea.

The earth will shake with the noise of Edom’s fall,

and its cry of despair will be heard all the way to the Red Sea.

The earth will quake from the sound of their falling.

A cry of distress! Their voice will be heard at the Red Sea.

The earth is moved at the noise of their fall,

At the cry the noise thereof was heard in the Red sea.

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