I recently picked up a second-hand copy of a book published posthumously, written by Anthony de Mello, a Jesuit priest from India who was world-renowned for his leadership of prayer retreats. It is titled “Contact with God” and he discusses all manner of prayers throughout the book.
Here’s some of his thoughts on petitionary prayer…
But no matter how meaningless petitionary prayer may seem to the philosopher, it begins to take on meaning to those who practice it assiduously, with child-like faith. Once you have discovered the power there is in prayer, you are not likely to be disturbed by philosophical difficulties connected with the why and wherefore. You have tried it out and it works. It brings you that “peace beyond understanding” that Paul speaks of, that “fulness of joy” that Jesus promised to those who exercised the prayer of petition. Having experienced this, you are quite content to continue asking for all you need, trusting that your heavenly Father loves you far more than any earthly father has ever loved his child.”
I like that description of the confidence that comes to those who keep at their prayers and begin to see God show His loving and faithful hand at work.