Dora Bas Rivka Silver O'H
This is the third and final Psalm in the series of songs that begin "do not destroy." David starts by referring to the incident in which Saul sent soldiers to arrest him, as recounted in I Samuel 19. He prays to be saved from the troops who were waiting for him to emerge from his house. Bloodthirsty people seek to kill David, not because of anything he has done to deserve it. They publicly prepare to persecute an innocent man - G-d can easily see this is true. David asks that G-d rouse Himself to action against treacherous people.
The soldiers surrounded David's house all night, like a pack of wild dogs. They boldly spew evil about David because they think there will be no consequences. But G-d knows better and He laughs at their plans, just as He laughs at the nations who scheme against Israel. G-d holds all the cards (my metaphor here, not David's), so David waits for G-d to act. David is confident that G-d will rescue him and that he will see his oppressors fall. David would prefer that they not be struck down suddenly and be forgotten; he would rather that their punishment serve as a moral example to the people. They should be trapped by their own evil plots and their own arrogance. They should be destroyed in stages until they are finally gone so that all will see and recognize that it was the work of G-d.
Just as Saul's soldiers surrounded David's house to capture him, the nations of the world will one day surround Jerusalem (at the time of Gog and Magog, as described in Ezekiel 38-39). They seek to consume and satisfy themselves. This doesn't concern David; he will trust in G-d and sing His praises. G-d has all the power and David is confident that He will treat him with kindness and rescue him.