Prayer is either a sheer illusion or it is a personal contact between embryonic, incomplete persons (ourselves) and the utterly concrete Person. Prayer in the sense of petition, asking for things, is a small part of it; confession and penitence are its threshold, adoration its sanctuary, the presence and vision and enjoyment of God its bread and wine.
In prayer God shows Himself to us. What He does is learned from who He is.

C.S. Lewis, The World's Last Night