Since happiness is nothing else than the enjoyment of the Supreme Good, and the Supreme Good is above us, no one can enjoy happiness unless he rise above himself, not, indeed, by a bodily ascent, but by an ascent of the heart. But we cannot rise above ourselves unless a superior power raise us. However much, then, the steps of our interior progress may be well-ordered, we can do nothing unless divine aid support us. This divine aid is at hand for all who seek it with a truly humble and devout heart, that is by sighing for it in this vale of tears by fervent prayer. Prayer, then, is the mother and origin of every upward striving of the soul.

—Saint Bonaventure, Itinerarium mentis in Deum, I.1