as I do sometimes, you could do worse than consult the Catechism of the Catholic Church (CCC). In sixteen short paragraphs (150–165), the CCC lays out the anatomy of faith: skeleton, musculature, nervous system, heart, lungs, all internal organs.
Along the way it calls a remarkable collection of witnesses for your journey: Thomas Aquinas, St. Augustine, John Henry Newman (pictured), Abraham, the Blessed Virgin Mary. They’re all here in fewer than six footnoted, cross-referenced pages of gold.
Leave it to Aquinas to sum up the interplay of divine grace and human will that is required: “Believing is an act of the intellect assenting to the divine truth by command of the will moved by God through grace.” (158) That amazing formula begins from its back end: grace which, still working backward, moves the will, which commands the intellect to assent to divine truth.
Faith, in other words, is a game of tennis, in which God serves and we need to engage our freedom and all of our human resources to keep the ball moving back and forth—with “the interior helps of the Holy Spirit,” an awkward phrase but clear in its simplicity.
In this divine game of tennis, the only rule change is, He always serves.
The CCC likens faith to marriage. I can relate. In this marriage uniting our will to divine grace, God provides “motives of credibility,” the translation of a Latin phrase that means “external proofs of his Revelation.” In marriage, we receive moments of great joy, like grace, and if we are open to life, we receive children, which we call miracles. Faith is just the same. To buttress ours, God gives us “the miracles of Christ and the saints, prophecies, the Church’s growth and holiness, and her fruitfulness and stability.”
But you might say the Church has not always been holy. She has not always grown. Like my marriage, I would say. But I am still married. We don’t abandon the United States because of a single corrupt administration or faulty politician. Likewise, we may choose not to abandon our faith despite an overzealous inquisition or a shocking scandal.
Staying in the game is always our choice. God will play as long as we stay on the court.
There are paragraphs here on faith and science, faith and freedom, faith and the eternal life—but none more moving than “perseverance in faith” (162):
Faith is an entirely free gift that God makes to man. We can lose this priceless gift, as St. Paul indicated to St. Timothy: “Wage the good warfare, holding faith and a good conscience. By rejecting conscience, certain persons have made shipwreck of their faith.” To live, grow, and persevere in the faith until the end we must nourish it with the word of God; we must beg the Lord to increase our faith; it must be “working through charity,” abounding in hope, and rooted in the faith of the Church.