Why Are There Seven Days In A Week?

This question has occupied the curious and the history fanatics for years. There is no easy answer to why most places now use a seven-day week. But many historical narratives point to the Babylonians who lived and created thousands of years ago.

Supposedly, the people of this region were astronomers on a level not many other civilizations reached. The Babylonians were also considered excellent in the study and use of math. These people and others were able to track the passage of time by observing the stages of the moon, which gives us the months of the calendar most people know today.

It is reported that eventually the Babylonians wanted to section off smaller portions of time so they started to look at dividing the month into smaller pieces. The cycle of the moon does not last exactly “one month” or an even 30 days. In fact, a moon cycle is 29 and ½ days. Apparently the people of Babylonia decided to divide the month into seven days to get as close as they could to four even parts of a moon cycle.

There was a less-successful movement for the 10-day week, but the seven-day variety was adopted by other groups outside the Babylonian settlements. So that version of dividing the month into seven-day weeks was the most popular and enduring.

The calendar we use, with seven-day weeks and 12 months, is commonly known as the Gregorian calendar, though some have referred to it as the calendar of the Common Era. A week containing seven days existed before this calendar, when the emperor in Rome, Julian, established his own calendar. This seven-day week was adopted when many began to adopt the Gregorian in the 1500s.

Further support for the seven-day week came with the adoption by the Jews. This use of the now-common seven days was not necessarily in everyday use during and after the time when Christ was born in the Middle East. But there is some historical record of seven-day periods being referred to. There has been some connection made to seven planets, stars and moons identified in the sky. It is believed by some that astronomers in the very early period of man’s time on earth actually identified five planets other than the Earth, along with the sun and the moon. This gave them the number “7.”

The days are named with this celestial planning in mind. Sunday, Monday (moon day) etc. It is widely believed that the seven-day division of time started as early as 2400 B.C. Of course it didn’t hurt that the great emperor Constantine adopted the seven-day week and the resulting calendar. The influence of his court and his long rule was so strong that this way of measuring time stood as the benchmark for Europe. It is since been transferred to nearly every country in the world. With the spread of British, Spanish and Portuguese influence during the years of discovery, the calendar we now use, with its seven-day week, traveled around the globe.

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