Telling Time in the Bible

Jewish and Roman timekeeping in the 1st Century

Introduction

In the Bible you’ll often read phrases like “the 3rd hour of the day” (Acts 2:15) or “about the 11th hour” (Mat 20:6), but if you try to match these hours up with our modern 3 o’clock or 11 o’clock, you’ll quickly get confused. The reason is because the Jews and the Romans of the 1st Century A.D. tracked time differently than us. They didn’t have precise digital clocks or Apple watches on their wrists. Roman and Jewish timekeeping was reckoned according to sundials and water clocks. In this short article, we’ll discuss how the ancients kept time, how the Roman and Jewish systems differed, and how to make sense of the “hours” mentioned in the Bible.

The first important thing to point out is that the Jews and Romans started their days at different times:

The Jewish Day

The Jewish day started at sunset and ended at the sunset of the next day. They always assigned 12 hours to the daylight and 12 hours to the night, no matter what time of year it was. This resulted in something called the relative or seasonal hour.

“A relative hour has no fixed radical, but changes with the length of each day - depending on summer (when the days are long and the nights are short), and in winter (when the days are short and the nights are long). Even so, in all seasons a day is always divided into 12 hours, and a night is always divided into 12 hours, which inevitably makes for a longer hour or a shorter hour” (https://handwiki.org/wiki/Astronomy:Relative_hour_(Jewish_law)).

When the Bible mentions a specific hour of the day, it is almost always using Jewish time (John’s gospel may have some exceptions), therefore:

• The 3rd hour of the day (about 3 hours after sunrise) = roughly 9:00am our time.

• The 6th hour of the day (about 6 hours after sunrise) = roughly 12:00pm (noon) our time.

• The 9th hour of the day (about 9 hours after sunrise) = roughly 3:00pm our time.

The Roman Day

The Roman day began at midnight and ended the following midnight (like our time). However, the ancient Romans also assigned 12 hours to the day and 12 hours to the night, which resulted in relative/seasonal hours. The length of their daytime “hour” was longer in the summer and shorter in the winter. The nighttime hours were further divided into 4 night watches: (1) Evening watch, (2) Midnight watch, (3) Cock-crow watch, and (4) Morning watch.

Time Keeping Methods

In a world without watches, the Jews and Romans used sundials and water clocks to keep track of the hours. Sundials were very popular and easy to use. Once properly adjusted, the sundial would cast a shadow indicating the hour of the day based on the position of the sun in the sky. Sundials worked great, but they had one big weakness, they only worked when the sun was out. Water clocks (clepsydra) were used to track time during the night. A water clock uses a container with marking on the inside. Water flows out of the container at a constant pace (through a hole or outlet). The amount of time that has passed can be determined based on the remaining water level.

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