Pope John Paul II
Fides et Ratio §2
Fides et Ratio: On the Relationship Between Faith and Reason
2 The Church is no stranger to this journey of discovery, nor could she ever be. From the moment when, through the Paschal Mystery, she received the gift of the ultimate truth about human life, the Church has made her pilgrim way along the paths of the world to proclaim that Jesus Christ is “the way, and the truth, and the life” ( Jn 14:6). It is her duty to serve humanity in different ways, but one way in particular imposes a responsibility of a quite special kind: the diakonia of the truth . This mission on the one hand makes the believing community a partner in humanity's shared struggle to arrive at truth; and on the other hand it obliges the believing community to proclaim the certitudes arrived at, albeit with a sense that every truth attained is but a step towards that fullness of truth which will appear with the final Revelation of God: “For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall understand fully” ( 1 Cor 13:12).
Source: Fides et Ratio (Vatican.va)