“I am with you always, to the end of the age.” This promise of Christ never ceases to resound in the Church as the fertile secret of her life and the wellspring of her hope. As the day of Resurrection, Sunday is not only the remembrance of a past event: It is a celebration of the living presence of the Risen Lord in the midst of His own people.
Thus the Lord unites us with Himself through the Eucharist—Sacrament and Sacrifice—and He unites us with Himself and with one another by a bond stronger than any natural union. Thus united, He sends us into the whole world to bear witness, through faith and works, to God's love, preparing the coming of His Kingdom and anticipating it, though in the obscurity of the present time.
From Go in Peace: A Gift of Enduring Love by John Paul II, © 2003 Loyola Press.