Prayer addressed to a man presupposes a certain intimacy that may afford the petitioner an opportunity to present his request. But when we pray to God, the very payer we send forth makes us intimate with Him, inasmuch as our soul is raised up to God, converses with Him in spiritual affection, and adores Him in spirit and truth. The familiar affection thus experienced in prayer begets an inducement in the petitioner to pray again with yet greater confidence.
[Thomas Aquinas, Compendium Theologiae II.2, in Aquinas's Shorter Summa, Vollert, tr., Sophia Institute Press (Manchester, NH: 2002) p. 335.]
