(Reblogged here in full because of the brevity.)
This is another coronation song. The wording suggests a rather impromptu celebration of Jehovah’s reign based on some recent miraculous deliverance. In the Ancient Near East, a ruler asserted his dominion in the form of giving laws. However, it was nothing like modern Western legislation, but the ruler would declare what kinds of things would get his attention. He would then promptly pass judgment on any pending cases, not least charges of disloyalty against those who refused to declare allegiance upon his taking the throne. A king’s law presumed a personal loyalty to him and a desire to please him. This image is necessary to understand the expressions in this psalm.
The first verse emphasizes the celebration of some mighty deliverance of Jehovah’s people. He did it by His own hand, not by hiding behind some army of men. This was no mere announcement, but an assertion by power itself. The next two verses loudly proclaim that He demonstrated the power to defend His domain; there is no way anyone anywhere on this earth can dispute it. In particular, He showed His intention to defend Israel and His divine grant to her. Let none dare challenge them in their place.
The next triplet of verses encourages everyone to make a joyful noise with whatever musical talents they might possess. There is mention of ancient instruments and we might surmise this was composed before the Exile.
Indeed, it does seem to echo the sentiments of Isaiah’s latter chapters in the final trio of verses. In typical Hebrew fashion, Creation itself is personified in various elements. How easily Westerners forget that ancient people believed Creation was a living thing, and God Himself used such language. The oceans, rivers and mountains thunder with His praise; do we listen? How could we not join in this celebration? Behold, He comes to assert His dominion over all Creation — mercy to the loyal, but wrath on those who oppose Him.