What Day of the Week is It?
Note: The days of the week do not have the same names that our modern calendars give them, so I attempt to use these names throughout this section. The days of the week are named based upon their relation to Dominica (Sunday), Monday is Feria (first), Tuesday is Secunda (second), Wednesday is Tertia (third), Thursday is Quarta (fourth), Friday is Sexta (Fifth) and Saturday is Sabbatum (Saturday/Sabbath[1]).
In the middle ages, calendars were not simply printed yearly for purchase by anyone who wanted them. Much like many other medieval manuscripts, calendars needed to be commissioned and were typically placed at the beginning of Books of hours and Psalters. Thus it was important that these calendars were less specific and reusable each year, thus these calendars do not have the days of the week listed by their names. Rather, the column of letters (A-G) that runs down the left hand side of the page, is meant to stand for the day of the week. In order to tell what day of the week it was by looking at the calendar, an individual would need to know what letter the year was. The letter of the year was determined by looking at the first day of the year and seeing what day of the week that day was, using that day to determine the first Dominica of the year and what letter that day lands on, and that would be the letter of the year and every Dominica for that year would also fall on that letter day. (Special Note: Leap years had 2 dominical letter the first one was valid from January 1-February 24th and the second from February 25- the end of the year.; The second letter would be the letter before the first, so if the first dominical letter for the year was C, the second would be B.)
To help you understand this lets take UCR 012R and use it to determine the dominical number for 2015. For 2015 January 1st (The 1st of the Kalends) was a Quarta (Thursday) thus January 4th (The 2nd of the Kalends) would be Dominica. Thus 2015 would be a “D” year, so “D” would be the letter for Dominica for the entirety of the year.
And now it's time to talk about what started off as my biggest question:
What are those Numbers on the left?
[1] Saturday, or the Sabbath Day, according to biblical sources was set apart by God for worship and to be kept as holy. It was a biblical commandment that on the seventh day of the week should be set apart as a day of rest, no work was to be done that could (or would) be done any other day of the week. (Note: because clocks were not existent before our modern age, days ran from sunset to sunset.) In our modern setting, resting on the Sabbath day would translate to not doing school work, housework, yardwork, or any other “chore” that requires labor from sunset on Friday to sunset on Friday. Exodus 20:8-11 follows: “8Remember the Sabbath day by keeping it holy. 9 Six days you shall labor and do all your work, 10 but the seventh day is a sabbath to the Lord your God. On it you shall not do any work, neither you, nor your son or daughter, nor your male or female servant, nor your animals, nor any foreigner residing in your towns. 11 For in six days the Lord made the heavens and the earth, the sea, and all that is in them, but he rested on the seventh day. Therefore the Lord blessed the Sabbath day and made it holy.”
Source(s):
Poole, R. L. (1921). Medieval Reckonings of Time. (C. Johnson, & J. Whitney, Eds.) New York, New York: The MacMillan Company.
Poole, R. L. (1921). The Days of the Week. In R. L. Poole, C. Johnson, & J. P. Whitney (Eds.), Medieval Reckonings of Time (pp. 17-20). New York, New York: The MacMillan Company.
The Holy Bible, New International Version. Grand Rapids: Zondervan House, 1984. Print.