Shrove Tuesday

Shrove Tuesday, the last of the days before Lent,
Is for thinking of sins that one needs to repent.
So from what did the holiday’s title derive?
Why, the preterit form of dated verb “shrive,”
Which refers to the freeing from guilt once confessed.
I can see why this name isn’t favored the best.
Many call it “Fat Tuesday” or French “Mardi Gras,”
As before a big seasonal fast, they will gnaw
On some rich, fatty foods, the traditional one
Being pancakes. That sure went from solemn to fun!