Biblical Tefach: Amazing ‘Common Constant’ Found Among Ancient Storage Jars In Israel

The team did 3-D scans of 307 Iron-Age jars found in Khirbet Qeiyafa (Judah Kingdom; early 10th century BC), "hippo" jars from northern Israel (Israelite Kingdom, 9th Century BC—nicknamed for their large size and loop handles which resemble hippopotamuses) and royal Judah Kingdom storage jars (8-7th Century BC).

The researchers observed large variations between the jars—even those from the same time period and geographic region.

Only one measure remained constant:

the averaged inner-rim diameter which always measured, with a standard deviation, between 8.85 and 8.97 centimeters.

There are many theories regarding this puzzle.

Bird's Eye View of Khirbet Qeiyafa - Courtesy of Khirbet Qeiyafa Expedition

The archaeologists obtained data on the standard measure of a modern man's palm, the team tapped measurements taken by the USA Army when ordering gloves for their soldiers, the mean value being 8.67±0.48 cm, which is consistent with the measurements taken from the ancient jars. However, there is another ancient aspect that may explain the connection between uniform neck diameters.

It is based on the highly-regarded and observed purity laws in The Old Testament. The Book of Numbers deals with the question: What is the status of jars that were left in the vicinity of a corpse—are they impure or pure?

"This is the law, if a man dies in a tent, anyone entering the tent and anything in the tent shall be unclean for seven days. Any open vessel which has no seal fastened around it becomes unclean." (Numbers 19: 14-15)

In his Code of Jewish Law called the “Mishnah Torah”, Maimonides says that  the Tefach was the size of the opening of a ceramic jar.:

“According to the Oral Tradition, it was taught that the verse is speaking only about a ceramic container, for it is a container that contracts impurity only through its opening.”

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