Catechism of the Catholic Church §2611 — excerpt
The prayer of faith consists not only in saying "Lord, Lord," but in disposing the heart to do the will of the Father. Jesus calls his disciples to bring into their prayer this concern for cooperating with the divine plan.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.