Reins. (that is, kidneys). In the ancient system of physiology, the kidneys were believed to be the seat of desire and longing, which accounts for their often being coupled, with the heart. Psalms 7:9; Psalms 26:2; Jeremiah 11:20; Jeremiah 17:10, etc.
More than 4,500 subjects and proper names are defined and analyzed with corresponding Scripture references. Bible students have used "Smith's Bible Dictionary" since its introduction in the 1880s, making it a trustworthy classic.Wikipedia
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