WEIGHTS AND MEASURES
Measures of Volume. Measurements of volume were originally made by estimated handfuls. Eventually containers (jars, baskets, etc.), which held an agreed upon number of handfuls were used as the standard measure. The terms used for such measures were frequently taken from the name of the containers.
The Israelites adapted the Mesopotamian system of measure of volume from the Canaanites. Their system contained several major designations for measuring dry volume.
Homer - The standard unit for dry measure (Ezek 45:11-14; Hos 3:2). This unit contained about 220 liters (6 1/4 bushels). It was a large measure weighing the equivalent of the normal load a donkey could carry. In Lev 27:16, a homer of barley is worth 50 shekels of silver. In Num 11:32 God provided quail so generously for his people that they could gather ten homers of them. Isaiah's prophecy of only an ephah of wheat from a homer of seed was a sign of God's judgment (Isa 5:10).
Kor - The same size as the homer (Ezek 45:14, cor; measure, KJV). The kor was used to measure flour (1 Kings 4:22), wheat, and barley (2 Chron 2:10; 27:5).
Ephah - a unit equal to one-tenth of a homer (Ex 29:40; deal, KJV; Isa 5:10).
Seah - a unit of uncertain capacity, but one-third of an ephah is probably correct (1 Sam 25:18; 1 Kings 7:1; measure, KJV, RSV, NEB, NASB).
Omer - a unit equal to one-tenth of an ephah (Ex 16:36). Another Hebrew word, issaron, translated "one-tenth of an ephah," (Ex 29:40; Lev 14:10; Num 15:4) was a dry measure of similar size to the omer.
(from Nelson's Illustrated Bible Dictionary, Copyright (c)1986, Thomas Nelson Publishers)
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