Pope St. John Paul II
“We see still more clearly the reason why the entire sacramental life of the Church and of each Christian reaches its summit and fullness in the Eucharist. For by Christ’s will there is in this Sacrament a continual renewing of the mystery of the Sacrifice of himself that Christ offered to the Father on the altar of the Cross, a Sacrifice that the Father accepted, giving, in return for this total self-giving by his Son, who ‘became obedient unto death’, his own paternal gift, that is to say the grant of new immortal life in the resurrection, since the Father is the first source and the giver of life from the beginning.”
Source: Pope St. John Paul II, REDEMPTOR HOMINIS, 3/4/79