Tefach

Biblical and Talmudic units of measurement were used primarily by ancient Israelites and appear frequently within the Hebrew Bible as well as in later Judaic scripture, such as the Mishnah and Talmud. These units of measurement are still an important part of Jewish life today. There is much debate within Judaism, as well as by outside scholars, about the exact relationship between measurements in the system and those in other measurement systems, such as the English units system used in the United States of America. Classical statements, such as that an Etzba was seven barleycorns laid side by side, or that a Log was equal to six medium-sized eggs, are so indefinite and vague as to be nearly useless. Nevertheless, the entire system of measurement corresponds almost exactly with the Babylonian system, and in all probability the Israelite measurement system was derived from the Babylonian measurement system, with some lesser level of influence from the Egyptian system. It may therefore be assumed that the relationship between the Israelite measurements and contemporary units is the same as the relationship between the Babylonian system and contemporary units.

Note: The listed measurements of this system range from the lowest to highest acceptable halachic value, in terms of conversion to either English or SI units.

The original measures of length were clearly derived from the human body — the finger, hand, arm, span, foot, and pace — but since these measures differ between individuals, they are reduced to a certain standard for general use. The Israelite system thus used divisions of the digit or fingerbreadth (Hebrew: אצבע, Etzba; plural etzba'ot), the palm or handbreadth (Hebrew: טפח, Tefah/Tefach; plural Tefahim/Tefachim), the span (Hebrew: זרת, Zeret), the ell (Hebrew: אמה, Amah, plural Amot), the mile (Hebrew: מיל, Mil; plural milin), and the parsa (Hebrew: פרסה, Parasa). The latter two are loan words into the Hebrew language, and borrowed measurements - the Latin mille, and Iranian parasang, respectively; both were units of distance, and thus varied according to terrain and stride length, and, in the case of the parasang, also on the speed of travel.

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