Faith as visio is a way of seeing the whole that shapes our relationship to "what is," that is, to God. Faith as fidelitas is faithfulness to our relationship of God. And faith as fiducia is deepening trust in God, flowing out of a deepening relationship with God. . . . Seeing, living, trusting and centering are all related in complex ways. They are all matters of the heart, and not primarily the head.
— Marcus J. Borg, The Heart of Christianity