I Learned Something New

I have used the term “red letter day” numerous times in my life, without truly knowing its origin. I finally looked it up, and it turns out that a red letter day was one annotated in red in illuminated scripts in the middle ages:

The term came into wider use in 1549 when the first Book of Common Prayer included a calendar with holy days marked in red ink. For example, Annunciation (Lady Day), 25th March, was designated in the book as a red-letter day.

Pretty interesting, if you ask me!

(Source: http://www.phrases.org.uk/meanings/red-letter-day.html)