SUNDAY, JUNE 19: For Western Christians, the Sunday after Pentecost recalls the fundamental dogma of Christianity; it is today, on Trinity Sunday, that all members of the Holy Trinity are honored. In one of the most complex mysteries of Christianity, the faithful contemplate God the Father, God the Son and God the Holy Spirit—three divine and equal persons in one God. (Get a Catholic perspective at FishEaters.) Trinity Sunday is recognized in all Western liturgical churches, and for most, it ushers in Ordinary Time on the Church calendar. (Wikipedia has details.) Vestments today are white.
The early Church dedicated no specific day to the Holy Trinity, although Thomas Becket ordered a festival for this purpose during his lifetime. The popularity of this day spread throughout Christianity, and soon, the Church had embraced it. (Looking for something to do with your family? CatholicCulture.org has ideas for themed food, activities and more.)
Symbols of the Trinity, including shamrocks, the pansy, an equilateral triangle, will be used in abundance today.
Originally published at readthespirit.com, an online journal covering religion and cultural diversity.