The balance between protest or expression of pain, and plea or request, is the reverse of that which characterizes Christian prayer. Christians are reticent about telling God things that God presumably knows, though they are then oddly unrestrained about itemizing what God should do even though they recognize that God could work this out. Prayer psalms suggest that the aim of prayer is to get God to decide to take action rather than persisting in inaction, and the object of expressing pain and protest is to achieve that. They imply that if God can be provoked to act, God can be left to work out precisely what to do. Thus pleas characteristically express themselves in three rather general terms that correspond to the three directions of the protest. They urge God to listen instead of ignoring or abandoning, to deliver the suppliant, and to act against the people who are causing the suppliant trouble, in order to put right a world that is out of kilter.
– John Goldingay, Psalms Vol. 1: 1-41 (BCOTWP), 62