Commentaries:
The psalm begins with a question. The psalmist has evidently been observing something in life, and he is quite bothered about it. Perhaps he has been praying and thinking about it for quite a long time. What has been bothering him is: Why do proud, evil people prosper? Why does not God take action? Why do they seem to receive the good things of life? The benefit we get from the psalmist's musings and meditations is instruction on the way the proud act.
John W. Ritenbaugh
Faith (Part Six)