[Greek] θώραξ (thōrax): breastplate, armor, trunk; Eph.6:14, 1Thess.5:8, Rev.9:9,17
Fresco of an ancient Macedonian soldier (thorakitai)
Background Information:
Greek Hellenism: This term can be found in both a literal and metaphorical sense. Throughout history, examples of armor include leather (with metal studs), bronze, and chain mail. Strength and lightness are the two qualities required for good armor. The area of the body between the abdomen and the neck is called the thorax. Aristotle claimed that the thorax encased the mortal soul. The thorax is the seat of courage. The courageous person doesn’t fear an especially noble death in battle.
Old Testament: This is also used literally and metaphorically in the Old Testament. The Phillistine Goliath wore a coat of chain mail. Armor, once exclusively used by the nobility, is later used in the army of Israel. Righteousness is metaphorically identified as a breastplate. Essentially, Yahweh will deploy His righteousness to bring salvation to His community and the nations, and bring the evil to justice. The imagery of armor denotes a battle. Righteousness is understood in an activist sense.
Goliath had a bronze helmet on his head and wore a bronze corselot of scale armor (1Sam.17:5). Then Saul clothed David in his own tunic, putting a bronze helmet on his head and arming him with a coat of mail (1Sam.17:38). There shall be a selvage, woven as at the opening of a shirt (Ex.28:32). He put on justice as a breastplate, salvation, as the helmet on his head; he clothed himself with garments of vengeance, wrapped himself in a mantle of zeal (Isa.59:17).
New Testament: This term is used metaphorically in Paul’s letters and literally in the book of Revelations. A locust’s chest (thorax) is described like an iron breastplate. In 1Thess 5:18 Paul presents the image of the Christian as a soldier of Christ (milites Christi) who must be ready for battle. In Eph.6:14 one must put on the breastplate of faith and love, which comes from Isa.59:17. This Christian attitude provides the right means of protection. Enclosed by this protection, one will be secure against evil spirits and temptation.
Scripture:
“These locusts had chests like iron breastplates.” Rev.9:9
Locusts, like other insects and bugs, are uniquely identified anatomically by their thorax.
“So stand fast with your loins girded in truth, clothed with righteousness as a breastplate.” Eph.6:14
One must adopt the armor of Christian righteousness to protect against evil and temptation.
Thorax, thoractic
Conclusion:
With the development of warfare, there inevitably comes the development (evolution) of armor, leading to chain mail. However, their medical lack of understanding gave way to erroneous conclusions about physical anatomy. The heart was also thought to be the seat of emotions.
It is significant that the Old Testament develops the notion of the breastplate of righteousness. This imagery provides a clear picture of a battle between good and evil.
In the New Testament, Paul further develops this idea as the Christian becoming a soldier of Christ. The Christian needs to wear righteousness as armor in the Christian life.