From new Encyclical: “Lumen Fidei”
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The dialogue between faith and reason
32. Christian faith, inasmuch as it proclaims the truth of God’s total love and opens us to the power of that love, penetrates to the core of our human experience. Each of us comes to the light because of love, and each of us is called to love in order to remain in the light. Desirous of illumining all reality with the love of God made manifest in Jesus, and seeking to love others with that same love, the first Christians found in the Greek world, with its thirst for truth, an ideal partner in dialogue. The encounter of the Gospel message with the philosophical culture of the ancient world proved a decisive step in the evangelization of all peoples, and stimulated a fruitful interaction between faith and reason which has continued down the centuries to our own times. Blessed John Paul II, in his Encyclical Letter Fides et Ratio, showed how faith and reason each strengthen the other.[27] Once we discover the full light of Christ’s love, we realize that each of the loves in our own lives had always contained a ray of that light, and we understand its ultimate destination. That fact that our human loves contain that ray of light also helps us to see how all love is meant to share in the complete self-gift of the Son of God for our sake. In this circular movement, the light of faith illumines all our human relationships, which can then be lived in union with the gentle love of Christ.
33. In the life of Saint Augustine we find a significant example of this process whereby reason, with its desire for truth and clarity, was integrated into the horizon of faith and thus gained new understanding. Augustine accepted the Greek philosophy of light, with its insistence on the importance of sight. His encounter with Neoplatonism introduced him to the paradigm of the light which, descending from on high to illumine all reality, is a symbol of God. Augustine thus came to appreciate God’s transcendence and discovered that all things have a certain transparency, that they can reflect God’s goodness. This realization liberated him from his earlier Manichaeism, which had led him to think that good and evil were in constant conflict, confused and intertwined. The realization that God is light provided Augustine with a new direction in life and enabled him to acknowledge his sinfulness and to turn towards the good.
All the same, the decisive moment in Augustine’s journey of faith, as he tells us in the Confessions, was not in the vision of a God above and beyond this world, but in an experience of hearing. In the garden, he heard a voice telling him: "Take and read". He then took up the book containing the epistles of Saint Paul and started to read the thirteenth chapter of the Letter to the Romans.[28] In this way, the personal God of the Bible appeared to him: a God who is able to speak to us, to come down to dwell in our midst and to accompany our journey through history, making himself known in the time of hearing and response.
Yet this encounter with the God who speaks did not lead Augustine to reject light and seeing. He integrated the two perspectives of hearing and seeing, constantly guided by the revelation of God’s love in Jesus. Thus Augustine developed a philosophy of light capable of embracing both the reciprocity proper to the word and the freedom born of looking to the light. Just as the word calls for a free response, so the light finds a response in the image which reflects it. Augustine can therefore associate hearing and seeing, and speak of "the word which shines forth within".[29] The light becomes, so to speak, the light of a word, because it is the light of a personal countenance, a light which, even as it enlightens us, calls us and seeks to be reflected on our faces and to shine from within us. Yet our longing for the vision of the whole, and not merely of fragments of history, remains and will be fulfilled in the end, when, as Augustine says, we will see and we will love.[30] Not because we will be able to possess all the light, which will always be inexhaustible, but because we will enter wholly into that light.
34. The light of love proper to faith can illumine the questions of our own time about truth. Truth nowadays is often reduced to the subjective authenticity of the individual, valid only for the life of the individual. A common truth intimidates us, for we identify it with the intransigent demands of totalitarian systems. But if truth is a truth of love, if it is a truth disclosed in personal encounter with the Other and with others, then it can be set free from its enclosure in individuals and become part of the common good. As a truth of love, it is not one that can be imposed by force; it is not a truth that stifles the individual. Since it is born of love, it can penetrate to the heart, to the personal core of each man and woman. Clearly, then, faith is not intransigent, but grows in respectful coexistence with others. One who believes may not be presumptuous; on the contrary, truth leads to humility, since believers know that, rather than ourselves possessing truth, it is truth which embraces and possesses us. Far from making us inflexible, the security of faith sets us on a journey; it enables witness and dialogue with all.
Nor is the light of faith, joined to the truth of love, extraneous to the material world, for love is always lived out in body and spirit; the light of faith is an incarnate light radiating from the luminous life of Jesus. It also illumines the material world, trusts its inherent order and knows that it calls us to an ever widening path of harmony and understanding. The gaze of science thus benefits from faith: faith encourages the scientist to remain constantly open to reality in all its inexhaustible richness. Faith awakens the critical sense by preventing research from being satisfied with its own formulae and helps it to realize that nature is always greater. By stimulating wonder before the profound mystery of creation, faith broadens the horizons of reason to shed greater light on the world which discloses itself to scientific investigation.
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