Where is there a “Reformation Day” in the Bible?
The day Jesus threw the money changers and prostitutes out of the temple was one.
Piffle...you’re grasping at straws...
Where is a “St Michael-mass” in the Bible? It, too, is a high Mass holiday.
Every place where the prophets or the apostles or Christ himself has to correct an error that has crept into the church. In other words, lots and lots of places.