Catechism of the Catholic Church §2559 — excerpt
"Prayer is the raising of one's mind and heart to God or the requesting of good things from God." But when we pray, do we speak from the height of our pride and will, or "out of the depths" of a humble and contrite heart?
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.
Also cites: St. John Damascene, Defide orth. 3, 24: PG 94,1089C · St. Augustine, Sermo 56, 6, 9: PL 38, 381