Priestly breastplate

The priestly breastplate (Hebrew: חֹשֶׁן‎ ẖošen) was a sacred breastplate worn by the High Priest of the Israelites, according to the Book of Exodus. In the biblical account, the breastplate is sometimes termed the breastplate of judgment, because the Urim and Thummim were placed within it. These stones were, at times, used to determine God’s will in a particular situation (see Exodus 28:30). It should be noted that using these stones did not always determine God's will (see 1 Samuel 28:6). If any other way was not given by God, the high priest would find God's guidance.

According to the description in Exodus, this breastplate was attached to the ephod by gold chains/cords tied to the gold rings on the ephod's shoulder straps, and by blue ribbon tied to the gold rings at the belt of the ephod. The biblical description states that the breastplate was also to be made from the same material as the Ephod—embroidery of 3 colors of dyed wool and linen—and was to be ⅓ of a cubit squared, two layers thick, and with four rows of three engraved gems embedded in gold settings upon it, one setting for each stone. The description states that the square breastplate was to be formed from one rectangular piece of cloth—⅓ of a cubit by ⅔ of a cubit, folded so that it formed a pouch to contain the Urim and Thummim.

The Hebrew term for the breastplate, חֹשֶׁן‎ (ḥōšen), appears to be named from its appearance, probably derived from the same source as Arabic حسن‎ (ḥasuna), meaning "to be beautiful". The 19th-century German biblical scholar August Dillmann thought that it was more likely to be derived from the Hebrew word חֹצֶן‎ (ḥōṣen), meaning "fold", relating to its function.

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