Breastplate, a term applied in the Auth. Vers. to two very different pieces of equipment.
I. Sacerdotal.-The official pectoral of the Jewish high-priest is called חשֶׁן, cho'shen, prop. ornament, being a gorget adorned on the outside with twelve gems, and hollow within, where were deposited the sacred lots "Urim and Thummim" (q.v.); hence more fully called the breastplate of judgment (Ex 28:15 sq.; Le 8:8; Sept. λογεῖον; Philo, λὀγιον; but fully λογεῖον κρίσεως in Ecclus. xl, 10). SEE EPHOD. It was a piece of very rich embroidered work, about ten inches square, and made double with a front and lining, so as to answer for a pouch or bag, in which, according to the rabbins, the Urim and Thummim were enclosed. The front of it was occupied by the twelve precious stones, on each of which was engraved the name of one of the tribes. They were placed in four rows, and divided from each other by the little golden squares or partitions in which they were set. The two upper corners of the breastplate were fastened to the ephod, from which it was never to be loosed (Ex 28:28), and the two lower corners to the girdle. The rings, chains, and other fastenings were of gold or rich lace. It was called the memorial (Ex 28:12,29), inasmuch as it reminded the priest of his representative character in relation to the twelve tribes. Josephus repeats the description (Ant. 3:7, 5), Grecizing the Heb. term by ἐσσήνης, and translating it by λόγιον. A full discussion of the subject may be found in Braunii Vestitus Sacerdotum Hebrcorum, pt. ii, ch. 7. SEE HIGH-PRIEST.
II. Military.-As a piece of defensive armor "breastplate" is the rendering in the Auth.Vers. only of שַׁריָן, shiryan', prob. gleaming (Isa 59:17; "harness," 1Ki 22:34; 2Ch 18:33), apparently a full coat of mail (q.v.), but according to the Sept. (θώραξ, which is the term thus rendered in Eph 6:14; 1Th 5:8; Re 9:9), a breastplate. Kindred and probably equivalent are the terms שַׁריוֹן, shiryon' ("coat of mail," 1Sa 17:5,38; "habergeon," 2Ch 26:14; Ne 4:16 ), and שַׁריָה skiryah' ("habergeon," Job 41:28 ). The full form occurs in the description of the arms of Goliatht שַׁריוֹן קִשׂקִשַּׂים, a "coat of mail," literally a "breastplate of scales" (1Sa 17:5; comp. ver. 38). SEE MAIL. It may be noticed that this passage contains the most complete inventory of the furniture of a warrior to be found in the whole of the sacred history. Goliath was a Philistine, and the minuteness of the description of his equipment may be due either to the fact that the Philistines were usually better armed than the Hebrews, or to the impression produced by the contrast on this particular occasion between this fully-armed champion and the wretchedly appointed soldiers of the Israelite host, stripped as they had been very shortly before both of arms and of the means of supplying them so completely that no smith could be found in the country, nor any weapons seen among the people, and that even the ordinary implements of husbandry had to be repaired and sharpened at the forges of the conquerors (1Sa 14:19-22). The passage in 2Ch 18:33 is very obscure; the A. V. follows the Syriac translation, but the real meaning is probably " between the joints and the breastplate." Ewald reads " between the loins and the chest;" Sept. and Vulgate, "between the lungs and the breastbone." This word has furnished one of the names of Mount Hermon (see De 3:9; Stanley, Palest. p. 403), a parallel to which is found in the name θώραξ given to Mount Sipylus in Lydia. It is thought by some that in De 4:48, Sion (שַׂיאֹן) is a corruption of Shiryon. SEE ARMOR.
A similar piece of defensive armor was the tachara' (תִּחֲרָא), which is mentioned but twice-namely, in reference to the meil or gown of the priest, which is said to have had a hole in the middle for the head, with a hem or binding round the hole "as it were the 'mouth' of an habergeon" (תִּחֲרָא), to prevent the stuff from tearing (Ex 28:32). The English "habergeon" was the diminutive of the "hauberk," and was a quilted shirt or doublet put on over the head--Smith. SEE HABERGEON.
In its metaphorical application, as the breastplate is a piece of defensive armor to protect the heart, so the breastplate of God is righteousness, which renders his whole conduct unassailable to any accusation (Isa 59:17). Christians are exhorted to take to themselves ' the breastplate of righteousness" (Eph 6:14), and "the breastplate of faith and love" (1Th 5:8). Being clothed with these graces, they will be able to resist their enemies, and quench all the fiery darts of the wicked one; a beautiful simile.