Why the Week is Seven Days Long

Some say the answer is hidden among the stars, but so far, no astronomer has been able to train their telescopes on the universe and find an explanation. Some say the answer is here on earth in the ceremonies of some ancient culture or custom, but so far, anthropologists have only a few clues.

“Why is a week seven days long?”

The question sounds simple enough until you begin to search for the facts. Then you soon learn that the road to discovery comes to an abrupt end. Read along with me and see whether you can solve the mystery.

First, a quick review from high-school science: the earth rotates on its axis once every 24 hours. We call that span of time one day. Next, the moon circles the earth once every 30 days. So we call that span of time a moon-th, or a month. Finally, the earth orbits the sun once every 365 days and we call that span a year.

As you can understand, these divisions of time come about quite naturally and have been known and used by the human race since ancient times. But we are still no closer to answering the question, “Why a seven-day week? Why not a week of eight, nine, 10 or even 20 days?”

Concerning this question, anthropologists have uncovered some interesting clues. They have found that, indeed, some cultures have tried five-, six-, and eight-day weeks. Some tribes in West Africa tried a week a mere four days long. During Napoleon’s time, the French government experimented with a 10-day week. But, like the others, it was replaced by the standard seven-day week. Today the question of why a week has seven days still remains unanswered by scientists and scholars.

There is an answer, but strange as it may seem, it is found in only one place—the Bible. “By the seventh day God finished the work he had been doing; . . . And God blessed the seventh day and made it holy, because on it he rested from all the work of creating that he had done” (Genesis 2:2, 3). So there it is, the origin of the seven-day cycle we now call a week.

However, we still haven’t answered the question of why God made this repeating cycle we know as a week. Some think it was His way of repeating over and over again to an often-forgetful human family that they should remember their roots.

Human Memorials

Perhaps this point can be better understood by looking at some of the extraordinary ways men have tried to leave a memory of themselves to the world. Egypt’s pharaohs erected huge monuments called obelisks, hewn from a single piece of red granite, in order to leave glorious details of their battles and other achievements chiselled deep into the polished stone surface.

The Greeks used marble and bronze to produce likenesses of their heroes, athletes and philosophers. Their successors, the Romans, made a practice of preserving wax masks of ancestors and also hired sculptors to make personal statues to be displayed in front of their homes. Even today, shelling out several thousand dollars for an elaborate cemetery headstone is not uncommon.

From the time of the Egyptian pharaohs to the present, monuments, statues and markers have had basically the same reason for being—man wants the world to remember him.

God’s Memorial

Could the seven-day week be God’s method of reminding us to remember our Creator?

Imagine that you had had the challenge of making a permanent marker to be set up at the beginning of time in the Garden of Eden that would remind people throughout eternity that they were to forever remember and respect their Creator. You could have had the message chiselled into a huge stone, but it would have been subject to the deteriorating effects of heat in the summer, freezing cold in winter and of course, the eroding effects of rain.

Even if it survived the forces of nature, it would still have been subject, as were the pharaohs’ monuments, to human tampering. Hist­ory tells us that a conqueror thought nothing of chiselling out a predecessor’s achievements and changing battle accounts to suit himself.

So it seems that a stone marker, no matter how large, would not do. After all, we’ve managed to lose something as important as the original copies of the Ten Commandments, which God wrote in stone with His own finger. Besides, what language could you choose that would be understood by all peoples for all time?

Considering all the difficulties, don’t you think God had the best way when He created the seven-day week? The idea of seven days strung together like beads on the strand of time is so unique that humanity can never claim the idea to be of natural origin linked in some explainable way to the moon, sun or stars. Furthermore, we can see that the seven-day week exists entirely because of the Sabbath day.

The Sabbath can be compared to the period at the end of a sentence. It tells you when to stop. It’s the period at the end of the week—after six ordinary days, the Sabbath punctuates the week and says, Stop here. The seven-day week exists only because God appointed the Sabbath day to mark its conclusion. All the other days of the week are so ordinary that the Bible simply numbers them as first, second, third and so on (Genesis 1:5, 8, 13, etc.). The evidence seems abundant that the only source of the seven-day week is the supernatural work of God, the Creator.

Why Holy Time?

There’s another important aspect to the Sabbath God set aside at Creation: He blessed the day and made it holy. Several thousand years later, to make sure that human beings clearly understood the purpose and function of the Sabbath, God gave these instructions:

“Remember the Sabbath day by keeping it holy. Six days you shall labour and do all your work, 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 manservant or maidservant, nor your animals, nor the alien within your gates. 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” (Exodus 20:8–11).

Isn’t it puzzling that the only things that last are things we cannot touch, taste, hear, smell or see? The apostle Paul called them the invisible things of this world. The seven-day week and the reason it exists (the Sabbath day) are invisible, unchangeable markers on the unseen stream of time. Their existence will continue on into the era when the earth is made new, and beyond:

“ ‘As the new heavens and the new earth that I will make will endure before me,’ declares the Lord, ‘so will your name and descendants endure. From one New Moon to another and from one Sabbath to another, all mankind will come and bow down before me,’ says the Lord” (Isaiah 66:22, 23).

The seven-day week and the Sabbath will always remain a mystery for some. But those who accept God’s invitation to enter that oasis in time understand that God’s holy Sabbath and the seven-day week began in Eden, continue today, and are a definite part of the future throughout eternity.

Do We Still Keep Jesus’ Sabbath?

Think back to last Saturday, the seventh day of our week. Then go back a week, and another, and another, for 2000 years. Would the Sabbath Jesus kept have lined up in seven-day weekly cycles with our seventh day today? Today’s Saturday Sabbath keepers get that question now and then, and the answer is Yes, our Saturdays line up in seven-day cycles with Jesus’ Sabbaths.

We know this for at least three reasons:

• Chronologists tell us that there has been no change in the weekly cycle for more than 2000 years.
• Jews are very strict about keeping the seventh day, especially orthodox Jews, and today’s Jews still observe Sabbath on our Saturday.
• If people who observe the Sabbath on the seventh day in honour of Creation (genesis 2:1-3) are keeping the wrong day, then people who observe Sunday in honour of Christ’s resurrection are also keeping the wrong day