From Pope St. John Paul II’s encyclical Veritatis Splendor (1993):
No one can escape from the fundamental questions: What must I do? How do I distinguish good from evil? The answer is only possible thanks to the splendour of the truth which shines forth deep within the human spirit, as the Psalmist bears witness: “There are many who say: ‘O that we might see some good! Let the light of your face shine on us, O Lord'” (Ps 4:6).
The light of God’s face shines in all its beauty on the countenance of Jesus Christ, “the image of the invisible God” (Col 1:15), the “reflection of God’s glory” (Heb 1:3), “full of grace and truth” (Jn 1:14). Christ is “the way, and the truth, and the life” (Jn 14:6). Consequently the decisive answer to every one of man’s questions, his religious and moral questions in particular, is given by Jesus Christ, or rather is Jesus Christ himself, as the Second Vatican Council recalls: “In fact,it is only in the mystery of the Word incarnate that light is shed on the mystery of man. For Adam, the first man, was a figure of the future man, namely, of Christ the Lord. It is Christ, the last Adam, who fully discloses man to himself and unfolds his noble calling by revealing the mystery of the Father and the Father’s love”.1
Jesus Christ, the “light of the nations”, shines upon the face of his Church, which he sends forth to the whole world to proclaim the Gospel to every creature (cf. Mk 16:15).2 Hence the Church, as the People of God among the nations,3 while attentive to the new challenges of history and to mankind’s efforts to discover the meaning of life, offers to everyone the answer which comes from the truth about Jesus Christ and his Gospel. The Church remains deeply conscious of her “duty in every age of examining the signs of the times and interpreting them in the light of the Gospel, so that she can offer in a manner appropriate to each generation replies to the continual human questionings on the meaning of this life and the life to come and on how they are related”.4
1 Pastoral Constitution on the Church in the Modern World Gaudium et Spes, 22.
2 Cf. Dogmatic Constitution on the Church Lumen Gentium, 1.
3 Cf. ibid., 9.
4 Second Vatican Ecumenical Council, Pastoral Constitution on the Church in the Modern World Gaudium et Spes, 4.
— Veritatis Splendor 2