Every Advent, on December 17, there is a notable shift in the Church’s liturgy. Whereas the beginning of Advent focuses on personal conversion and the second coming of Christ, the final days of Advent are geared towards a more direct preparation and reflection on the Nativity of Christ. It is the most sacred time of the Advent season, a fact reiterated by the rich traditions developed in various cultures specially for these days. As a man of Puerto Rican descent, I experienced this first-hand. In Hispanic culture, December 17-23 is marked by the “Misa de Gallo” or “Mass of the Rooster.” For eight days, people from Spanish-speaking countries gather before dawn to celebrate Mass as a sign of our expectation for the coming Messiah, he who will be the New Dawn of salvation. I remember waking up with my mother at 4:30 a.m. to attend the liturgies every year, keeping vigil before the empty manger with over a hundred other parishioners at St. Catherine of Siena Mission in Kissimmee, Florida. It remains one of the most impressive experiences that I remember from my childhood.

Needless to say, the week leading up to Christmas is a special time in the Church’s liturgical life, typified by inspiring teachings on the profundity of the Incarnation of Jesus Christ and his fulfillment of Old Testament prophecy. Since the eighth century, these days have been characterized by the “O Antiphons,” a series of short declarations denoting different titles of Christ from the prophets. Each day honors a certain prophecy about the Messiah and the graces he comes to share with humanity. Each designation is preluded by the acclamation “O,” transmitting the joy, splendor, and wonder of receiving such a King. The antiphons are as follows:

December 17: O Sapientia
O Wisdom of our God Most High,
guiding creation with power and love:
come to teach us the path of knowledge!

December 18: Adonai
O Lord of the House of Israel,
giver of the Law to Moses on Sinai:
come to rescue us with your mighty power!

December 19: O Radix Jesse
O Root of Jesse’s stem,
sign of God’s love for all his people:
come to save us without delay!

December 20: O Clavis David
O Key of David,
opening the gates of God’s eternal Kingdom:
come and free the prisoners of darkness!

December 21: O Oriens
O Radiant Dawn,
splendor of eternal light, sun of justice:
come and shine on those who dwell in darkness and in the
shadow of death.

December 22: O Rex Gentium
O King of all nations and keystone of the Church:
come and save man, whom you formed from the dust!

December 23: O Emmanuel
O Emmanuel, our King and Giver of Law:
come to save us, Lord our God!

“O Wisdom of our God Most High!” Christ is the Wisdom of God made flesh. This correlates to the opening lines of John’s Gospel: “In the beginning was the Word, and the Word was with God, and the Word was God” (John 1:1). In Greek, “Word” is logos, which means “reason” or “logic.” Thus, Jesus is the way God thinks, the manifestation of God’s logic: “When you see me you see the Father” (John 14:9). In Christ, we see how God exists; he reveals the deepest secrets of God’s heart. This revelation reaches its fulfillment on the cross, when the full logic of God is on display. Christ crucified shows us what lies at the center of God’s genius—namely, sacrificial love. The source of divine power is selflessness and gift. To suffer is to be sanctified, to die is to be divine, to be laid down is to rise up. We are most ourselves when we are given for another. This is the Wisdom from on high, the great secret of the heavenly logos. There is a God, and he is love (1 John 4:8).

“O Lord of the House of Israel!” Jesus is the supreme Lord of Israel, the promised Messiah who will liberate nations and bring all people into a single fold. What was inscribed upon slabs of stone by the finger of God is now hewed within the flesh of a virgin by the grace of the Spirit. No longer will humanity look to the pages of law for its guiding principles. Our model lies in the small hands of the Christ-child destined to be pierced with rusted nail. The wood of the manger at Bethlehem is a harbinger of the wood of the cross at Calvary, that precious tree that will become a distaff upon which is woven the souls of sinners.

“O Root of Jesse’s stem!” God keeps his promises in grander ways than we can ever imagine. Did he not vow to exult the lineage of Abraham and reestablish the kingdom of David? How many centuries the Jews dreamed about God’s salvation, the glorious manner in which he would liberate Israel. Little did they know how radically God planned to get involved. He did not send an emissary or third-party. He sent his own Son—the Word became flesh. God himself came to us. The root of Jesse’s stem was watered with the blood of its gardener. Its produce harvested by the plow of the cross. The Holy Spirit speaks well through the author of Deuteronomy: “What other nation is so great as to have their gods near them the way the Lord our God is near us?” (Deut. 4:7). He is more near than we often realize. For he has joined himself to our very flesh.

 “O Key of David!” In the second book of Samuel, chapter 7, we witness a moving exchange between God and King David. The monarch recognizes his own comfort in a house of cedar while the Ark of the Covenant is residing in a tent. David sees this as a gross injustice and seeks to remedy the situation by erecting a worthier dwelling place for God. That same night, God’s utters a stirring exhortation through the prophet Nathan. The king will not build a house for the Lord. Rather, the Lord will build a house for the king and his descendants (2 Sam. 7:10-12). It will be a house of flesh that will establish an eternal dynasty. This promise is not only referring to Solomon. The early Church immediately recognized Christ as the true fulfillment of the pact between God and David. Jesus is the key of David’s line—forged by the divine locksmith—that unlocks the doors of heaven for all humanity.

“O Radiant Dawn!” The sun is a powerful symbol of the ancient world. All nascent civilizations revolved around it as the giver of day and nourisher of life. To see the sun’s rays burst over the horizon is a sign of hope amidst the darkness of night. They announce a new day and all the aspirations that accompany it. Light is especially significant to Judaism, as it is the first reality created by God: “Let there be light” (Gen. 1:3). With this declaration, all things are thrust into being. It is no coincidence that God made light before all else. For it is an analogy of his son “through whom all things were made” (Col. 1:16). The light of creation is a precursor to the Light of the World (John 8:12). The birth of Jesus is the dawn of ages that points to a new day of salvation.

“O King of all nations!” Sin divides. It disperses humanity and sets us apart from one another. Yet in Christ, we have a king who unites and gathers. Despite the varied backgrounds, cultures, languages, and traditions of this world, there is one reality that transcends every boundary: Catholicism. Jesus in his Church unites us universally with that unbreakable bond called mercy. Not as an ethereal abstract sentiment, but a concrete tangible reality. Whereas governments and political parties seek influence through power, Christ unites through a piercing of the heart and the common experience of redemption. Though people often disagree over the reasons why the world is broken, we do not disagree that it is broken. No matter how far apart we may drift in our theories, we are bonded by the shared need for salvation, and this is the impetus that inspires Catholic mission.

“O Emmanuel!” What is the greatest truth of Christianity? That God is with us. Not merely as an emotion or an idea, but actually with us—Body, Blood, Soul, and Divinity. It was not enough for God to dwell among us, speak with us, die for us. He still did more. His love had to go inside of us. The death of Calvary could not remain a memory. It had to be lived and consumed. For this reason, we have the Eucharist. It is in the Sacrifice of the Holy Mass that Emmanuel comes into the world. The Incarnation remembered historically on Christmas day is relived in every human soul each time they receive Communion. What the shepherds and wise men saw with their eyes, we receive in our bodies. The splendor that angels adore at a distance, we touch with our hands and taste with our tongues. This is what we celebrate before all else at Christmastime. It is not only about being with family and friends or exchanging gifts. At the center of this season is the profoundest of truths: that he who arranged the stars of the sky and set the cosmos in motion took the form of a child—for me. Before I was conceived in my mother’s womb, he was conceived in Mary’s womb—for me. This is who our God is and why we rejoice. For we once were lost and wandered the world searching for hope. Then, hope was born for us in a cave.