The Feast of the Holy Trinity

The Feast of the Holy Trinity developed slowly during the Middle Ages. Local observances existed in Germany and England from as early as the tenth century, but it was not established as a universal feast of the Western Church until 1334, when Pope John XXII ordered it observed on the octave (the eighth day) of Pentecost. That placement was deliberate: the feast stands at the exact hinge of the Church Year, where the great narrative of salvation history concludes and the long season of ordinary Christian living begins.

The liturgical color returns to white, sharply distinguishing Holy Trinity Sunday from the long series of green Sundays that follow in the Trinity season. The Proper Preface appointed for the day declares that we “worship the Trinity in person and the Unity in substance, of majesty coequal,” reminding the congregation that the Triune God is not to be explained by human reason but confessed in worship. The readings carry a strongly baptismal emphasis: both Matthew 28:16–20 and John 3:1–17 are the great lections of Holy Baptism, binding this feast inseparably to the sacramental work of Easter and Pentecost. The Athanasian Creed is traditionally associated with this feast, and its full recitation remains a salutary custom wherever it is still practiced.

In the year King Uzziah died, struck with leprosy for his arrogant intrusion into the temple, Isaiah is granted a vision of the true, immortal King. The Lord is described as rum and nasa’, “exalted and lifted up,” adjectives that in Isaiah apply only to God and, remarkably, to the Suffering Servant in Isaiah 52:13, pointing to the Incarnate Son enthroned before time. The seraphim (from saraph, “to burn”) cry the Trisagion, qadosh, qadosh, qadosh, which, while grammatically a superlative of holiness, is the Old Testament’s great adumbration of the Trinity: John tells us Isaiah saw the glory of the Son (John 12:41), and Paul declares the Spirit was speaking through him (Acts 28:25).

Isaiah’s cry of nidmeti, “I am ruined” or “I am struck dumb,” mirrors King Uzziah’s defilement, yet where the earthly king was cut off, God sends a seraph with a burning coal from the altar, pronouncing the Word of Absolution: “Your guilt is gone; your sin is atoned for.” The Hebrew verb tekuppar comes from kapar, the sacrificial root meaning to cover and propitiate. It is the same root as kippur in Yom Kippur. The altar that purifies Isaiah’s lips foreshadows the cross of Christ.

This passage is the grand doxological climax to Paul’s three-chapter meditation on God’s saving history with Israel and the Gentiles. His sustained logical argument dissolves at last into sheer worship through a series of three trinitarian triads: three attributes (riches, wisdom, and knowledge), three rhetorical questions expecting the answer “no one,” and three prepositions: ex autou, di’ autou, eis auton, “from him, through him, to him.” The Church Fathers, including Origen and Augustine, applied these prepositions trinitarianly: the Father as Source, the Son as Mediator, the Spirit as Goal and End.

God’s judgments are anexerauneta, “unsearchable,” a word found nowhere else in the Greek Bible, and His paths are anexichniastoi, “untraceable,” leaving no footprints for human reason to follow. Yet the Spirit searches these very depths (1 Corinthians 2:10). The doxology closes without a verb: autō hē doxa, “to him is the glory.” Paul does not say God receives glory; he declares the glory He already and eternally possesses.

Nicodemus approaches Jesus by night. In John’s Gospel, darkness is never merely a time of day but a theological condition. Jesus tells him he must be born anothen, a deliberate Greek double entendre meaning both “again” and “from above.” Nicodemus hears only the earthly sense; Jesus means the heavenly birth that only God can effect. The new birth comes ex hydatos kai pneumatos, “of water and the Spirit,” where a single Greek preposition binds water and Spirit inseparably together, pointing directly to Holy Baptism as a New Creation event: as the ruach hovered over the waters in Genesis and God breathed life into dry dust, so the Spirit hovers over the baptismal waters to beget us as children of the Father.

The entire passage discloses the cooperative work of all three Persons. The Father sends the Son. The Son descends and will be hypsothenai, “lifted up,” a word in John’s Gospel that always means crucifixion and exaltation simultaneously. The Spirit, like a sovereign wind, blows where He wills, delivering through Word and Sacrament the salvation the Son won on the cross. The Trinity is not a philosophical puzzle to be solved but a saving reality to be entered through Baptism in the name of the Father, Son, and Holy Spirit.