From Verbum Domini:
Creation is the setting in which the entire history of the love between God and his creation develops; hence human salvation is the reason underlying everything. Contemplating the cosmos from the perspective of salvation history, we come to realize the unique and singular position occupied by man in creation: “God created man in his own image, in the image of God he created him: male and female he created them” (Gen 1:27). This enables us to acknowledge fully the precious gifts received from the Creator: the value of our body, the gift of reason, freedom and conscience. Here too we discover what the philosophical tradition calls “the natural law”. In effect, “every human being who comes to consciousness and to responsibility has the experience of an inner call to do good” and thus to avoid evil. As Saint Thomas Aquinas says, this principle is the basis of all the other precepts of the natural law. Listening to the word of God leads us first and foremost to value the need to live in accordance with this law “written on human hearts” (cf. Rom 2:15; 7:23). Jesus Christ then gives mankind the new law, the law of the Gospel, which takes up and eminently fulfils the natural law, setting us free from the law of sin, as a result of which, as Saint Paul says, “I can will what is right, but I cannot do it” (Rom 7:18). It likewise enables men and women, through grace, to share in the divine life and to overcome their selfishness.
Pope Benedict XVI writing about the The Twelfth Ordinary General Assembly of the Synod of Bishops, which met in the Vatican from 5-26 October 2008, and had as its theme: “The Word of God in the Life and Mission of the Church.”