We're all supposed to sing unto God, How terrible art thou in thy works! through the greatness of thy power shall thine enemies submit themselves unto thee (v. 3). To each his own, I guess. We're reminded of the events of Exodus, which apparently was a test, along with a time when he let people ride over their heads. Once again, why does a supposedly omniscient god need to test us, exactly?
Praise be to god for judging us!
Finally, a few of the good things god does: adopts orphans, protects widows, frees slaves and brings rain. He also let his people win a war so they could take home the spoils, even the shepherds.
Next, a paean to hills: god makes hills because he wants to live in one, apparently. Then we get an accounting of god's 20 000 chariots and angels and how he used them to capture people so they'd give him prezzies.
Then more threats: god will give his enemies head wounds, especially if they have hair. Then the righteous will have to dip their feet in the blood and their dogs will eat it. Yum! What's the point of all this? Silver (v. 30). That's right. God wants silver from his enemies.
David's family has rejected him because of his religious beliefs. In the next few verses, we get a better idea of why: he's consumed by zealotry, he's been fasting and he wears sackcloth. I have to say that if any member of my family was acting like that, I'd get him or her into cult deprogramming right away, but that probably didn't exist back then so the next best thing was to reject your crazy son and go back to worshipping your pantheon of nature gods.
The rest of society has also noticed David's peculiarity: he's even a drinking song. I'd read 50 more Psalms just to know what the lyrics are but alas the bible disappoints once again. People won't even give him proper meat and wine, just gall and vinegar.
And what does he get for all this? Nothing! God won't answer him. He's reduced again to cursing his enemies, this time wishing blindness, Parkinson's disease, homelessness and death.
Next, David cheaps out on sacrifices, saying prayers are better than beef. I would kick him out of my barbecue if he pulled that one.
David wants god to hurry up and curse his enemies. Fortunately, the chapter is only 5 verses.