This page was last updated on 17 July,2018
The duration of an hour
Gen 1:5 And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.
Almost at the very beginning of the Bible God defines day as the period of a calendar day that has light. That obviously means dark in no way is part of that definition.
John 11:9 Jesus answered, Are there not twelve hours in the day? If any man walk in the day, he stumbles not, because he sees the light of this world.
Jesus said that every day has 12 hours. But we know from experience that the duration between sunrise and sunset can vary several hours a day.
We all know the expression “the days get longer”. That never refers to the 24-
The answer to this riddle is very simple. Hours varied in duration. They seldom were exactly 60 minutes. There are, as far as I know, two main views on how that’s done.
The second view has little support, and some math quickly show why.
Jerusalem sunrise and sunset on 21 June: 05:34-
Jerusalem sunrise and sunset on 21 December: 06:34-
A 4 hour difference can’t be spread over 2 hours. An hour can’t be made shorter than 0 minutes.
That leaves the first option.
The longest day is 854 minutes. That’s 71.2 minutes per hour.
The shortest day is 604 minutes. That’s 50.3 minutes per hour.
The number of hours was very important to the ancient Jews, because many law related things were done at set times of the day. For example, each and every day 2 lambs were sacrificed to God.
All things relating to that were spaced out in parts of 3 hours over the day. When we look at crucifixion day we see that things all happened on the border of 3 hour blocks. Obviously no coincidence because because those rituals always pointed to crucifixion day.
While the hours kept changing in duration the lamb was always killed at the exactly the ninth hour. That ninth hour was always the at the same percentage of daylight.
The Temple was closed during the dark hours so sacrifices had to be done in the daylight hours. Below a simple table showing the Temple rituals at set hours and how they point to Christ.
Relative hour (Hebrew singular: sha’ah zemanit; plural: sha’ot -
Another feature of this ancient practice is that, unlike the standard modern 12-
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