The one thing that distinguishes Christianity from all other ideologies and religions is our profession of the Trinity. We believe in one God, but we also believe that that one God is three: Father, Son, and Holy Spirit.
The Trinity is also the starting place of Christian action. At the end of Matthew’s Gospel, we read that Christ gives his disciples the Great Commission: go baptize and make disciples in the name of the Trinity. Much in the same way that an emissary of a king or queen comes in the name of their monarch, Christians are instructed to act in the name of the Triune God. We act in the name of the Trinity when we baptize, bless, consecrate, and pray in general.
It’s strange however that so many preachers dread giving sermons on Trinity Sunday. As I prepared this sermon, I noticed that the prevailing sentiment amongst priests and religious educators is to avoid making any kind of definitive statement about the Trinity. “It’s a mystery,” as it seems nearly everyone agrees.