Dr. David Murray, on his blog Head Heart Hand, offers some very good reasons why the Psalms are so impactful in a Christian's life. The whole piece is worthwhile reading as we think of that age-old dilemma of expressing how we feel about something.
Whether it is feelings of loss or despair, loneliness or fear, joy or thanksgiving... all who come to the Psalms discover that the words which capture our experiences and emotions are already composed for us by the One who identifies with us in our suffering and thanksgiving!
"Despite hundreds of new Christian songs, of every possible genre, being composed every year, the ancient Psalms are experiencing somewhat of a revival in various places. Why?
I believe the main reason is their therapeutic value; in a day of so many disordered emotions, worshippers are discovering how the Psalms minister so powerfully to their emotional lives."
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The Psalms express the full range of human emotions
"The Psalms contain an incomparably rich mixture of extreme and varied emotions: grief and joy, doubt and confidence, loneliness and fellowship, despair and hope, fear and courage, defeat and victory, complaint and praise, etc.
Is it any wonder that Calvin called the Psalms “an Anatomy of all Parts of the Soul”? As he explained: “There is not an emotion of which anyone can be conscious that is not here represented as in a mirror. Or rather, the Holy Spirit has here drawn to life all the griefs, sorrows, fears, doubts, hopes, cares, perplexities, in short, all the distracting emotions with which the minds of men are wont to be agitated.”
Read the whole piece online here: http://headhearthand.org/blog/2012/02/13/therapeutic-praise/