“On this mountain the Lord of hosts will provide for all peoples a feast of rich food and choice wines, juicy, rich food and pure, choice wines.” (from Isaiah 25, Office of Readings)
In Hebrews 12, we learn that the mountain of the Lord of hosts in Isaiah’s prophecy is the city of the living God, the heavenly Jerusalem, and the assembly of the first-born enrolled in heaven. The Church tells us in Sacrosanctum Conclium that the Holy Sacrifice of the Mass together with the Divine Office is a foretaste of this heavenly liturgy that takes place in the Jerusalem above.
In other words, it is in the earthly liturgy that we are provided in advance with the feast of rich food and choice wine to strengthen us on our pilgrimage to our heavenly homeland. Indeed, every time we assist at the sacrifice of the Mass or pray the Divine Office, we ascend the mountain of the Lord of hosts where God feeds us and takes away the reproach of his people. It is thus the greatest source of immeasurable joy and gladness that we can know on this side of heaven.
But for us to truly share in this feast as members of the new covenant, all that stands opposed to God must be “trodden down as a straw is trodden down in the mire” (Isaiah 25, Office of Readings). “The bows of the mighty” must be broken and all pride must be “cast down to the nether world” (Old Testament Canticle, Morning Prayer). To “worship the Lord, the King who is to come" (Invitatory Antiphon), we must prepare for His advent when “He will bring to light what is hidden in darkness and manifest the intentions of hearts” (Reading, Evening Prayer).
We are thus given the season of Advent not to “pass judgment on others before the time of the Lord’s return, “ but to prepare our own hearts for He who “has promised men divinity, mortals immortality, sinners justification, the poor a rising to glory” (St. Augustine, Office of Readings). This wondrous exchange was first made when the eternal Son of God assumed our human flesh in the lowly manger at Bethlehem. But it is brought about in each of us every time we participate in the Sacred Liturgy. Let us then use this time of Advent to prepare our hearts for the coming of the Lord, so that we may partake of the rich food and choice wine of the Mass and offer to God fitting praise in and through the Divine praises He has given us in the Office.