by Pope John Paul II
81. The Church lives by the Eucharist, by the fullness of this Sacrament, the stupendous content and meaning of which have often been expressed in the Church's Magisterium from the most distant times down to our own days. However, we can say with certainty that, although this teaching is sustained by the acuteness of theologians, by men of deep faith and prayer, and by ascetics and mystics, in complete fidelity to the Eucharistic mystery, it still reaches no more than the threshold, since it is incapable of grasping and translating into words what the Eucharist is in all its fullness, what is expressed by it and what is actuated by it. Indeed, the Eucharist is the ineffable Sacrament! The essential commitment and, above all, the visible grace and source of supernatural strength for the Church as the People of God is to persevere and advance constantly in Eucharistic life and Eucharistic piety and to develop spiritually in the climate of the Eucharist. With all the greater reason, then, it is not permissible for us, in thought, life or action, to take away from this truly most holy Sacrament its full magnitude and its essential meaning. It is at one and the same time a Sacrifice-Sacrament, a Communion-Sacrament, and a Presence-Sacrament. And, although it is true that the Eucharist always was and must continue to be the most profound revelation of the human brotherhood of Christ's disciples and confessors, it cannot be treated merely as an "occasion" for manifesting this brotherhood. When celebrating the Sacrament of the Body and Blood of the Lord, the full magnitude of the divine mystery must be respected, as must the full meaning of this sacramental sign in which Christ is really present and is received, the soul is filled with grace and the pledge of future glory is given. This is the source of the duty to carry out rigorously the liturgical rules and everything that is a manifestation of community worship offered to God himself, all the more so because in this sacramental sign he entrusts himself to us with limitless trust, as if not taking into consideration our human weakness, our unworthiness, the force of habit, routine, or even the possibility of insult. Every member of the Church, especially Bishops and Priests, must be vigilant in seeing that this Sacrament of love shall be at the center of the life of the People of God, so that through all the manifestations of worship due to it Christ shall be given back "love for love" and truly become "the life of our souls." Nor can we, on the other hand, ever forget the following words of Saint Paul: "Let a man examine himself, and so eat of the bread and drink of the cup."
82. This call by the Apostle indicates at least indirectly the close link between the Eucharist and Penance. Indeed, if the first word of Christ's teaching, the first phrase of the Gospel Good News, was "Repent, and believe in the gospel" (metanoeite), the Sacrament of the Passion, Cross and Resurrection seems to strengthen and consolidate in an altogether special way this call in our souls. The Eucharist and Penance thus become in a sense two closely connected dimensions of authentic life in accordance with the spirit of the Gospel, of truly Christian life. The Christ who calls to the Eucharistic banquet is always the same Christ who exhorts us to penance and repeats his "Repent." Without this constant ever renewed endeavor for conversion, partaking of the Eucharist would lack its full redeeming effectiveness and there would be a loss or at least a weakening of the special readiness to offer God the spiritual sacrifice in which our sharing in the priesthood of Christ is expressed in an essential and universal manner. In Christ, priesthood is linked with his Sacrifice, his self-giving to the Father; and, precisely because it is without limit, that self-giving gives rise in us human beings subject to numerous limitations to the need to turn to God in an ever more mature way and with a constant, ever more profound, conversion.