Pope Pius XII
Mystici Corporis Christi §72
Mystici Corporis Christi: On the Mystical Body of Christ
72 As by faith on this earth we hold fast to God as the Author of truth, so by Christian hope we long for Him as the fount of blessedness, "looking for the blessed hope and coming of the glory of the great God." It is because of this universal longing for the heavenly Kingdom that we do not desire a permanent home here below, but seek for one above, and because of our yearning for the glory on high that the Apostle of the Gentiles did not hesitate to say: "One Body and one Spirit, as you are called in one hope of your calling;" nay rather that Christ in us is our hope of glory.
Source: Mystici Corporis Christi (Vatican.va)