25 The Church needs to reflect upon itself and to become aware of its own extraordinary vitality. It must strive to gain a fuller understanding of itself if it is to do what it has to do and bring to the world the message of salvation and brotherly love. To use St. Paul's phrase, it must experience the indwelling presence of Christ: "May Christ find a dwelling place through faith in your hearts.'' (l3)
Source: Ecclesiam Suam (Vatican.va)