holidays
Sue -- Well, start with a lunar calendar (13 months of 28 days each) and put all the holidays on the new moon or the full moon. Then set the beginning of any "day" to be the evening prior (per Genesis: "It was evening and it was morning, the {x} day"). Then consider that every culture that arose anywhere there were distinct seasons has similar seasonal holidays. Autumn gives you a harvest festival (Rosh Hashonnah, All Saints Day/Halloween), mid-winter we-need-light festival (Channukkah a.k.a. Festival of Lights, Christmas, Saturnalia), spring yay-the-earth-comes-back-to-life fertility festival (Passover, Easter, May Day), and so on. Then take a religion whose church structure was finally destroyed by the Romans and whose cultural/religious/ethnic development has been controlled by 2K years of Diaspora, with every group getting the rules interpreted by their local rabbi ("teacher") and adopting the local country's culture. Confused yet? It gets better...