This work by St. Augustine was one of the first works he wrote as a presbyter. It does not have the lucidity of his later works but is much more convoluted. Still, his object is an important one and unsurprisingly relevant. He writes to a young man lately come out from the Manichean religion of which Augustine himself was previously a devotee. The Manichees derided the Catholic Church for inviting people to have faith. The Manichees promised instead that they would offer reason, logic, proof, and understanding. This appealed to Augustine in previous years but he began to notice a number of difficulties with their promise. First, it never quite delivered. Each time he asked a question they could never offer an adequate response. Often they would promise that when their master arrived he would be able to answer the future saint's questions. But when the teacher finally arrived Augustine found him no wiser than the rest, though a deal more eloquent. Second, he realized that there are simply a number of things which cannot be understood by reason until the heart is first cleansed or prepared by faith. If one insisted on entirely understanding another before getting married, s/he would never get married. They are a great many things which are the reward, not the prerequisite, of commitment. It is only by giving oneself to the beloved that his/her knowledge of the beloved increases and deepens. It is no mistake, therefore, that the relationship of God with his people is so often described as a marriage. We learn to trust Him before we learn Him. Too often by insisting upon understanding we insist upon circumstances which forestall the granting of the very thing we seek. We do not understand in order to believe. Rather, according to that ancient maxim Cred Ut Intelligam, "We believe in order to understand."