Catechism of the Catholic Church
2558 "Great is the mystery of the faith!" The Church professes this mystery in the Apostles' Creed (Part One) and celebrates it in the sacramental liturgy (Part Two), so that the life of the faithful may be conformed to Christ in the Holy Spirit to the glory of God the Father (Part Three). This mystery, then, requires that the faithful believe in it, that they celebrate it, and that they live from it in a vital and personal relationship with the living and true God. This relationship is prayer.
For me, prayer is a surge of the heart; it is a simple look turned toward heaven, it is a cry of recognition and of love, embracing both trial and joy. 1
2559 "Prayer is the raising of one's mind and heart to God or the requesting of good things from God." 2 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? 3 He who humbles himself will be exalted; 4 humility is the foundation of prayer. Only when we humbly acknowledge that "we do not know how to pray as we ought," 5 are we ready to receive freely the gift of prayer. "Man is a beggar before God." 6
2560 "If you knew the gift of God!" 7 The wonder of prayer is revealed beside the well where we come seeking water: there, Christ comes to meet every human being. It is he who first seeks us and asks for a drink. Jesus thirsts; his asking arises from the depths of God's desire for us. Whether we realize it or not, prayer is the encounter of God's thirst with ours. God thirsts that we may thirst for him. 8
2561 "You would have asked him, and he would have given you living water." 9 Paradoxically our prayer of petition is a response to the plea of the living God: "They have forsaken me, the fountain of living waters, and hewn out cisterns for themselves, broken cisterns that can hold no water!" 10 Prayer is the response of faith to the free promise of salvation and also a response of love to the thirst of the only Son of God. 11