"By the gift of the Holy Spirit at Pentecost the Church was born and set out upon the pathways of the world,
yet a decisive moment in her taking shape was certainly the institution of the Eucharist in the Upper Room.
Her foundation and wellspring is the whole Triduum paschale, but this is as it were gathered up, foreshadowed and “concentrated' for ever in the gift of the Eucharist.
In this gift Jesus Christ entrusted to his Church the perennial making present of the paschal mystery.
With it he brought about a mysterious “oneness in time” between that Triduum and the passage of the centuries."