Sunday’s Solemnity of the Holy Trinity has an interesting history.
As Fr. John Hardon points out in his Modern Catholic Dictionary, the origins of the celebration of Trinity Sunday goes all the way back to the Arian heresy of the fourth century, when Arius denied the divinity of Christ by denying that there are three Persons in God. Arius said that Jesus was only a human being.
To stress the doctrine of the Trinity, the Fathers of the Church composed prayers and hymns that were recited every Sunday as part of the Divine Office, the official prayer of the Church. For hundreds of years, this was the only way this feast was commemorated, and it was limited to monasteries and by ordained clerics in dioceses around the world. There was no special effort made to celebrate it publically, via a Sunday Mass, for example.
Eventually, a special version of this Divine Office began to be celebrated on the Sunday after Pentecost … but it was still limited to monasteries, convents, etc.
At the request of St. Thomas a Becket (1118-1170), the Catholic Church in England was granted permission to celebrate Trinity Sunday as an actual Sunday Mass. The celebration of Trinity Sunday was made universal by Pope John XXII (1316-34).
Just thought you’d like to know …
Pray faithfully, love deeply, laugh often!
Fr. Herb, C.S.C.