While we have been following a 7 day week calendar for what seems to be forever, scholars have been trying to find out how did Moses come out with the idea of a 7 day cycle of Sabbath in the first place. For “scholars”, divine revelation is not an acceptable answer, so a hunt for an alternative is necessary. The first theory is that Moses copied it from other ancient cultures, most likely the Egyptians. The scholars tried hard, but could find no records in any other ancient culture of anything similar to either a socially accepted work-rest cycle or the number 7 being somehow special.
The other theory is that 7 has some mathematical or astronomical significant. This theory failed also. The number 10 make sense, because human and monkeys have 10 digits. The number 2, 3, 4, 6, 12, 24, and even 60 have been used as units of measurement of time, mostly because they can be easily constructed with simple geometry (i.e. you can divide a line or an angle using straight lines and a pair of compasses into halves and thirds, thus making the measurement of movement of sun, moon and stars easy). But the number 7 is particularly difficult to construct geometrically. The best theory is that 7 is almost one quarter of the lunar cycle (one lunar cycle = 29.53 days). But 10 days (= one third of lunar cycle) would be a much more convenient and accurate unit for that.
So we are stuck with the theory that either Moses really suck at astronomy or the number 7 comes from divine revelation.
Regardless, the number 7 is the signature of Sabbath. As in the coming weeks we go through scriptures to look for the number 7, we will discover that Sabbath is much more than a weekly religious ceremony but an elaborate system for a sustainable economy.