understanding rest sabbath

For Bible believers the significance of the seventh day, the Sabbath, as a day of rest is not an issue. It is clearly stated in the scripture, no arguments here. But for others it is unclear why the seventh day of the week is a rest day. Why?

It seems to me that the Sabbath has its origins in something very Cosmic. It seems to me that it is based on the lunar cycle. It takes 28 days approximately for the moon to make one complete cycle around the zodiac. If you count seven days from the beginning of the cycle the moon will be square its original position. This is a stressful aspect and it is right and proper to schedule a rest on that day. Now let’s count seven days after. In other words 14 days from the beginning of the cycle. Here, the moon will be in opposition to it’s original position.This is another stressful aspect and rest is certainly called for. Now let’s count another seven days. This would be the 21 days from the original starting point. On the 21st day the moon is again in stressful aspect to its original position. Again a day of rest is certainly logical. We haven’t dealt with the original position. Since this is the beginning of the cycle not necessarily a stress day but the beginning of the lunar cycle – beginnings should also be periods of rest, meditation, prayer etc. which is what the Sabbath is all about.