Catechism of the Catholic Church
163 Faith makes us taste in advance the light of the beatific vision, the goal of our journey here below. Then we shall see God "face to face", "as he is". 47 So faith is already the beginning of eternal life:
When we contemplate the blessings of faith even now, as if gazing at a reflection in a mirror, it is as if we already possessed the wonderful things which our faith assures us we shall one day enjoy. 48
164 Now, however, "we walk by faith, not by sight"; 49 we perceive God as "in a mirror, dimly" and only "in part". 50 Even though enlightened by him in whom it believes, faith is often lived in darkness and can be put to the test. The world we live in often seems very far from the one promised us by faith. Our experiences of evil and suffering, injustice and death, seem to contradict the Good News; they can shake our faith and become a temptation against it.
165 It is then we must turn to the witnesses of faith: to Abraham, who "in hope... believed against hope"; 51 to the Virgin Mary, who, in "her pilgrimage of faith", walked into the "night of faith" 52 in sharing the darkness of her son's suffering and death; and to so many others: "Therefore, since we are surrounded by so great a cloud of witnesses, let us also lay aside every weight, and sin which clings so closely, and let us run with perseverance the race that is set before us, looking to Jesus the pioneer and perfecter of our faith." 53
English Translation of the Cathechism of the Catholic Church for the United States of America © 1997, United States Catholic Conference, Inc.