Trinity Sunday: Western Christians honor Trinity, Orthodox mark Pentecost

Trinity Sunday window

A stained-glass window with a visual representation of the Holy Trinity. Photo courtesy of Wikimedia Commons

SUNDAY, JUNE 4: It’s been one week since Pentecost, and for Western Christians, this marks Trinity Sunday: a time to recognize a central and unfathomable mystery of the Christian faith. Believers hold that all members of the Blessed Trinity—the Father, the Son and the Holy Spirit—are equal, uncreated and infinite, and a celebration of the Christian doctrine of the Trinity is celebrated across Western liturgical churches.

Though the Holy Trinity is honored every Sunday, the early church observed no specific day in honor of this holy mystery until Thomas Becket (1118-70 CE) helped spread the idea of an observance of such a day, saying that the day of his consecration would be held as a new festival for the Holy Trinity. Even still, a day set aside solely for recognizing this mystery continued to vary in several regions until Pope John XXII accepted the festival into the official calendar of the Western Church, in 1334 CE.


White shines from the décor and vestments of most Western churches today, as the faithful ponder the one God that is three Persons. For many centuries, Christian leaders have taught that this mysterious truth must be believed by true followers of the faith, as a joyous Gospel passage proclaims that God’s nature has been revealed: “Going therefore, teach ye all nations, baptizing them in the Name of the Father and of the Son and of the Holy Ghost.”

It’s said that no mortal can truly grasp the concept of the Holy Trinity, but efforts can be made! Try picking a shamrock today, or a viola tricolor; light a candle with three flames; or decorate a home altar with symbols of the Trinity. has more ideas.

Note: Trinity Sunday falls the first Sunday after Pentecost in the Western Christian Church each year, and on Pentecost Sunday in the Eastern Orthodox Christian Church.

Trinity Sunday: Western Christians revere Trinity, Orthodox mark Pentecost

SUNDAY, JUNE 11: White banners are draped and vestments shine as a sign of purity as Western Christian churches worldwide celebrate Trinity Sunday. Note: In the Eastern Christian Church, Trinity Sunday is observed on the Sunday of Pentecost. A culmination of the Nativity, Epiphany, Resurrection, Ascension and Pentecost, Trinity Sunday calls to mind the role that each member of the Holy Trinity—the Father, Son and Holy Spirit—play in Christianity.

Many Christians are surprised to learn that the original writers of the New Testament did not use the term “Trinity” as it appears in mainline Christianity today. While the three elements of divinity, God and Christ and Holy Spirit, were a part of the faith from its early years, the famous theologian Tertullian (who lived and wrote in Africa) is widely credited as introducing the first full analysis of the Trinity in the early 3rd century. The doctrine wasn’t formalized among Christian leaders until the fourth century.

For centuries, church leaders argued that the Trinity was honored every Sunday. But, in the 12th century, Thomas Becket declared that the day of his consecration should be an annual festival in honor of the Holy Trinity. The observance spread through Western Christianity, and was placed in the general calendar in the 14th century.

There is, perhaps, nothing more central to the creed of the Christian faith—and yet, so elusive, in comprehension of it—than the Holy Trinity. Through the centuries, countless saints have attempted to teach about the Trinity. Among the most famous was a three-leaf clover that tradition says was used by St. Patrick.


On this one Sunday each year, many Christians around the world recite the Athanasian Creed (read it here). Some bake cloverleaf rolls to reflect the Trinity, or set the table with a centerpiece of triple-leaf flowers. For a Catholic perspective or to read Pope John Paul II’s writings on the Holy Trinity, go to