It is not enough just to sing the words without meaning them. Yet there are still many advantages to having hymns composed before a service instead of being made up on the spot–advantages like greater participation, assurance of doctrinal soundness, and compelling and memorable words. More than that, singing familiar hymns again and again actually enhances rather than diminishes their capacity to express the inarticulate longings of our hearts. If we can sing hymns written down in advance, without thinking that makes them fake or insincere, why not say prayers written down in advance?
The idea that liturgical prayers are in conflict with prayer from the heart, with really meaning what we say, is relatively new in Christian history. Jesus, the apostles, churches before and after the Reformation–all used fixed forms of liturgical prayer. For most of the last two thousand years, Christians have used liturgical prayers and spontaneous prayers, with liturgical prayers predominating in public worship and adding richness and depth to the spontaneous prayers used in private worship.
— Samuel L. Bray and Drew Nathaniel Keane, How to Use the Book of Common Prayer
Bologna 