The wicked are evil lying liars. They even plot bad deeds in their beds, which they don't lie in properly. But god is good and makes the beds of the righteous soft and comfortable.
Don't worry about evil-doers because god will cut them down like grass. I had no idea they were so concerned about lawn maintenance back then.
Blah, blah, prosperity doctrine, just believe in god and you won't go hungry. There's a good line about renouncing anger in verse 8, but then verse 11 informs us that the meek shall inherit the earth which, if you've ever seen a genuine emergency situation like Haiti or Pakistan recently, you'll know is patently untrue. The people fighting to get stuff off the trucks might get pummeled, but the ones queuing up calmly in the back are assured of getting nothing.
In the next couple of verses, we are informed that the wicked plot against the good, like, no shit Sherlock, they're evil, but that god laughs at them because he's going to punish them. Someday. In the future. Why not swift, immediate justice? David doesn't say.
A few things the wicked do: fail to repay loans and kill the righteous. Their punishment: god makes them stab themselves in the heart, breaks their arms and makes them infertile.
Rewards for the good: inheritance of the earth, food, children, wisdom, salvation.
Uh-oh, god's mad! And he made David sick as punishment. David's symptoms: arrows stuck in his body, a crushing sensation, generalised weakness, tired bones, seeping wounds, especially on his uh, penis, feebleness, a panting heart, blindness. He thinks the cure is god's attention. I think the attention of a naked Shunamite virgin would probably also help.
David once made a vow to stop talking. Would that he had kept it. Now he wants to know when he's going to die. Don't we all. Also, he wants to talk and for god to listen.
Now that he has started talking again, David can't seem to shut up. Here he brags about how much he loves god and evangelizes to everyone he meets.