Q: Greetings, Fr Paul.
What would be possible liturgically for a Parish celebration of a diamond anniversary of the church building which was not, and never will be, consecrated as it was not thought of as permanent ? However, there was a foundation stone blessed at the time, still in place.
It is not the diamond anniversary of the parish as a community of faith – that happened a few years ago.
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A: It would be appropriate to offer a Mass for Various Needs and Occasions when the calendar permits it. You could choose one of the first ones For Holy Church, 1E for example.
Or a Mass for Giving Thanks to God (49).
Given the special nature of the occasion, you could argue in favor of singing the Gloria.