Why is a week… “7 days”?
Bodie Hodge M.Sc., B.Sc., PEI
Biblical Authority Ministries, June 7, 2024
It’s so basic we don’t even think about it! A week is 7 days
and everyone knows that—even in remote cultures all over the world—a week is
still 7days! But why? Let’s look at this in more detail.
Day
Let’s start with the a “day”. A “day” is a night-day cycle
which consists of the earth rotating one full spin. God defined a day in
Genesis 1:5 as having an evening and a morning having both a cycle of darkness
and light.
In the old days, when the sun went down, it marked the
beginning of a new day. However, in the Northern Hemisphere, the farther north
you go, the more extreme the sunset is. It could be like 5 pm or as late 9:30 pm,
give or take a little bit here in the Midwest where I am. So, in the Western
World, we simply bump it back to Midnight (12:00 AM) to make sure its dark. Of
course, the extreme north in the summer the sun doesn’t even go down! But for
most people in North America, Europe, and Asia, the sun has set before midnight.
Month
The idea of a month is one revolution of the moon around the
earth. It is where we get the name month (think “moon-th”). The moon goes
around the earth about every 29.5 days so lunar calendars use alternating 29-
and 30-day month (lunar/luna means moon in Latin).
When you use a lunar calendar, by the time you get to the 12th
month, you only have 354 days (11 days short of a normal year)! So, it doesn’t
quite make a true year. So those using a lunar calendar have to add in an extra
month about every 3 years to correct the calendar so that it doesn’t drift.
A lot of ancient calendars (including Noah’s, e.g., Genesis
7:11-8:4) simply used a 30-day month for all 12 months (a type of solar
calendar—solar or more properly solaris/sol means sun in Latin). This
gets you to 360 days in a year (5 days short of a normal year) and they also
add an extra month (just not as often as the lunar calendar) to keep that
calendar from drifting and bringing it back to normal. This extra month is
called an “intercalary” month—think of it like an extra “December” every 6
years or so.
Year
The idea of a year is based on the earth going around the
sun one time. We map this exact moment by aligning our position yearly to the
constellations. A year is about 365.24 days. The ancient Egyptians at one point
adopted a 365-day year. So did the Romans (called the “Julian Calendar”) and
named for Julius Caesar. Our modern calendar (called the Gregorian Calendar) is
modification of the Julian Calendar with leap years, leap seconds, and so on to
correct it to make it even closer.
So simple enough:
· A “day”—the rotation of the earth 1 time
· A “month”—the time it takes the moon to go around the earth 1 time
· A “year”—the time it takes the earth to go around the sun one time
Week
But what about a week? Week has nothing to do with
any heavenly body and its motion! Instead, a week comes from one place:
the Bible. When God created everything, He did it over the course of 6 days and
rested for 1 day (instituted a rest period).
It wasn’t like an all-powerful God was worn out and needed a
break but His rest was one of reflection and refreshment on the accomplishment of
what He has done. Instead, He instituted rest for our benefit. In The Ten
Commandments, God told us why He did it—as a basis for our work week to give us
time to rest and refresh by taking a break from doing your normal work/customary
work (as it is oft stated when resting holidays also occurred; Exodus 20:11, e.g.,
Numbers 28:25).
After the Flood, a week
continued to endure in Noah’s day. When cultures were scattered by family groups
all over the world at the Tower
of Babel, they also took a week with them. This is why remote cultures such
as Amazon rainforest tribes, tundra peoples, or aboriginals of Australia still
utilized a week. It has been passed from generation to generation without too
many people thinking about it as a part of everyday culture.
A week comes from God and His Word. Anti-God cultures have
tried to change the week with little success. For instance, in France in 1792,
they tried a 10-day work week called “décades” (“deca” means ten).
It failed miserably and after 13 years of complete exhaustion and confusion,
they scrapped it. They went back to a 7-day week to the relief of the masses
while Napoleon was in control of the country.
The communist Soviets did something similar for 11 years.
They tried a continuous work week (called “nepreryvka”) in 1929 where
80% of the workforce was required to work on typical days of rest. Although
they had staggered rest across the week, it too demoralized everyone. In 1940,
the country returned to the 7-day week schedule.
God designed the day of rest for man and these failed
attempts show…a 7-day week works. Of course, God knew it would, He is
all-knowing after all.
