"Short shrift"

I just used this phrase in a conversation, then realized I had no idea what a shrift is. Turns out it's a penance, and the phrase has really cool medieval Catholic roots:

In early medieval times penances were long and arduous—lengthy pilgrimages and even lifelong exile were not uncommon — and had to be performed before absolution, not after as today. However, less demanding penances could be given in extreme situations; short shrift was a brief penance given to a person condemned to death so that absolution could be granted before execution.

Good to know.