"Time it was, and what a time it was, it was..."
~Paul Simon, Bookends~
In my post yesterday I wondered a bit "on the side" why, in the Book of Genesis, it says "and there was evening, and there was morning", instead of the other way round. (Did God work nightshift?) I did have it at the back of my head, that the Jewish ideas about when the day started were or are different from how we look at it today... So I checked it up. And thought I might as well share my findings:
In the era before the modern clock, a specific hour of the night could not be precisely known, whereas an hour of the day was easily determined by sighting the location of the sun. This meant that the day had to be reckoned either from the beginning of night or the beginning of day.
Both ways of looking at it existed in Biblical times. The Egyptians considered the day to start at sunrise. The Babylonians considered it to begin with the night. (The Israelites were under Egyptian influence for a while, but Babylonian later.)
In Jewish tradition, the day begins with the onset of night (the appearance of the stars), followed by the morning (which technically begins with the appearance of the North Star). Or, sunset and sunrise respectively.
So the Jewish Sabbath begins on Friday night and ends with the appearance of the stars on Saturday night; and the same is true for the major holidays.
Beginning the day with the night is also considered a metaphor of life itself. Life begins in the darkness of the womb, then bursts into the brightness of the light and eventually settles into the darkness of the grave, which, in turn, is followed by a new dawn in the world-to-come.
In the beginning God created the heavens and the earth. Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters. And God said: "Let there be light," and there was light. God saw that the light was good, and he separated the light from the darkness. God called the light "day" and the darkness he called "night". And there was evening, and there was morning - the first day. (Genesis 1:1-5)
+ a Swedish Encyclopedia of the Bible