CCC 2837 “Daily” (epiousios) occurs nowhere else in the New Testament. Taken in a temporal sense, this word is a pedagogical repetition of “this day,”1 to confirm us in trust “without reservation.” Taken in the qualitative sense, it signifies what is necessary for life, and more broadly every good thing sufficient for subsistence.2 Taken literally (epi-ousios: “super-essential”), it refers directly to the Bread of Life, the Body of Christ, the “medicine of immortality,” without which we have no life within us.3 Finally in this connection, its heavenly meaning is evident: “this day” is the Day of the Lord, the day of the feast of the kingdom, anticipated in the Eucharist that is already the foretaste of the kingdom to come. For this reason it is fitting for the Eucharistic liturgy to be celebrated each day.
The Eucharist is our daily bread. The power belonging to this divine food makes it a bond of union. Its effect is then understood as unity, so that, gathered into his Body and made members of him, we may become what we receive. .. This also is our daily bread: the readings you hear each day in church and the hymns you hear and sing. All these are necessities for our pilgrimage.4
The Father in heaven urges us, as children of heaven, to ask for the bread of heaven. [Christ] himself is the bread who, sown in the Virgin, raised up in the flesh, kneaded in the Passion, baked in the oven of the tomb, reserved in churches, brought to altars, furnishes the faithful each day with food from heaven.5
1 Cf. Ex 16:19-21.
2 Cf. 1 Tim 6:8.
3 St. Ignatius Of Antioch, Ad Eph. 20, 2 PG 5, 661; Jn 6:53-56.
4 St. Augustine, Sermo 57, 7: PL 38, 389.
5 St. Peter Chrysologus, Sermo 67 PL 52, 392; Cf. Jn 6:51.