Madam,
you asked me to tell you something about prayer. For us, human beings, words are necessary: not that they can convey our wishes to God, of whom he is unaware, or that they can change his intentions, but because they help us to look within ourselves and to become aware of our needs.
If you reflect on the requests contained in all holy prayers, I am sure you will find nothing that is not already included in the Lord's Prayer. When we pray, we can therefore use whatever words we like, but we must continually ask for the same things. Here we have no option to choose. In prayer, we find the eagerly sought fountain of life, if we maintain hope even though we do not yet see the things we hope for, and live in trust under the protective wings of God, in whom all our desires will be satisfied from the abundance of his house and the river of his blessings.
(St. Augustine /354–430/, letter to a certain noble lady, 411)