Adam Clarke on Psalms 29:10

The Lord sitteth upon the flood - יהוה למבול ישב Jehovah lammabbul yasheb, "Jehovah sat upon the deluge." It was Jehovah that commanded those waters to be upon the earth. He directed the storm; and is here represented, after all the confusion and tempest, as sitting on the floods, appeasing the fury of the jarring elements; and reducing all things, by his governing influence, to regularity and order.

Sitteth king for ever - He governs universal nature; whatsoever he wills he does, in the heavens above, in the earth beneath, and in all deep places. Every phenomenon is under his government and control. There is something very like this in Virgil's description of Neptune appeasing the storm raised by Juno for the destruction of the fleet of Aeneas. See at the end of this Psalm.