The psalm ends on a positive note:
He chose David his servant...to be the shepherd of his people Jacob...And David shepherded them with integrity of heart; with skilful hands he led them. (v.71f; TNIV)
So, all's well that ends well. Except it doesn't. The psalm only goes so far; it cuts off the history mid-stream. Knowing the rest of the story makes for depressing reading: even David was mired in sin and shame. Is there no answer? Is there no deliverer? Is the story destined to always remain the same? Is there no hope?
Thanks be to God, who delivers me through Jesus Christ our Lord! (Rom. 7:25 TNIV)