'We pray to God because we believe in him through Jesus Christ; that is to say, our prayer can never be an entreaty to God, for we have no need to come to him in that way. We are privileged to know that he knows our needs before we ask him. This is what gives Christian prayer its boundless confidence and its joyous certainty. It matters little what form of prayer we adopt or how many words we use, what matters is the faith which lays hold on God and touches the heart of the Father who knew us long before we came to him.
Genuine prayer is never "good works", an exercise or a pious attitude, but it is always the prayer of a child to a Father. Hence it is never given to self-display, whether before God, ourselves, or other people. If God were ignorant of our needs, we should have to think out beforehand how we should tell him about them, what we should tell him, and whether we should tell him or not. Thus faith, which is the mainspring of Christian prayer, excludes all reflection and premeditation.'
Dietrich Bonhoeffer, The Cost of Discipleship, p.109.