Each person is called to love as friendship and self-giving. Each person is freed from the tendency to selfishness by the love of others, in the first place by parents or those who take their place and, definitively, by God, from whom all true love proceeds and in whose love alone does man discover to what extent he is loved. Here we find the root of the educative power of Christianity: "Humanity is loved by God! This very simple yet profound proclamation is owed to humanity by the Church." In this way Christ has revealed his true identity to man: "Christ the new Adam, in the very revelation of the mystery of the Father and of his love, fully reveals man to himself and brings to light his most high calling."< The love revealed by Christ "which the Apostle Paul celebrates in the First Letter to the Corinthians... is certainly a demanding love. But this is precisely the source of its beauty: by the very fact that it is demanding, it builds up the true good of man and allows it to radiate to others." Therefore it is a love which respects and builds up the person because "Love is true when it creates the good of persons and of communities; it creates that good and gives it to others."< Married love thus becomes a power which enriches persons and makes them grow and, at the same time, it contributes to building up the civilization of love. But when the sense and meaning of gift is lacking in sexuality, a "civilization of things and not of persons" takes over, "a civilization in which persons are used in the same way as things are used. In the context of a civilization of use, woman can become an object for man, children a hindrance to parents...". (Pontifical Council for the Family: The Truth and Meaning of Human Sexuality, 1995).