2 Indeed, it is faith that allows us to draw near to the hidden mysteries of the divine life; it is faith that encourages us to hope for everlasting happiness; it is faith that strengthens and consolidates the unity of the Christian society in this transitory life, according to the Apostle: "One Lord, one faith, one Baptism." It is chiefly by reason of this divine gift that our grateful hearts of their own accord pour forth this testimony: "What shall I render to the Lord for all that he hath rendered unto me?"
Source: Fidei Donum (Vatican.va)