By Thomas Moll
Director of Content

The first Sunday after Pentecost has a name unlike any other feast on the church calendar. Most commemorations celebrate an event or a saint. Trinity Sunday celebrates who our God is: Father, Son, and Holy Spirit.

Trinity Sunday falls on May 31 this year, and the Rev. Dr. Thomas Ahlersmeyer shares a message titled, “Let God Be God!” on our “Worship Anew” program.

The feast has a surprisingly contested history. In the early medieval church, local celebrations of the Trinity were common, but Rome resisted making it a universally accepted observance for centuries — partly out of concern that singling out one Sunday for the Trinity implied the other Sundays were somehow less Trinitarian. (Fair point!) It wasn’t officially added to the Roman calendar until 1334 under Pope John XXII. Martin Luther kept the feast, and the Lutheran church calendar has observed it ever since as a fitting capstone to the great half of the church year.

The famous hymn “Holy, Holy, Holy!” — a staple of Trinity Sunday worship draws its text directly from Isaiah 6 and Revelation 4, where angelic voices cry out before the throne of God. The threefold “holy” (Sanctus) has been understood by the church as an implicit witness to the Trinity since the earliest centuries of Christian worship.

Lutherans confess the doctrine of the Trinity, not as a philosophical puzzle to be solved, but as the living God who speaks, saves, and sanctifies.

The Athanasian Creed — one of three ecumenical creeds — is traditionally read or sung on Trinity Sunday as a bold, comprehensive declaration of who God is.

“Holy, holy, holy, merciful and mighty! God in three persons, blessed Trinity!” (LSB #507:1).