νεφρός

From the study of Revelation 2:23

Range of meaning

Literally 'kidneys'. In Hebrew idiom (kelayot) and in Greek that follows it, the kidneys were the hidden seat of a person's deepest emotions, desires, conscience and private impulses: the parts of the self that never show on the surface. Hidden inside the body and wrapped in fat, they were a natural image for what lies deepest.

Against the English

KJV 'reins' is accurate (from Latin renes, 'kidneys'), but few modern readers know the word, and many think of horse reins. BSB and WEB use 'minds', NIV 'hearts and minds' in reversed order, and NLT 'thoughts and intentions'. These keep the idea of inwardness but lose the body image. 'Minds' also moves the word toward thinking, which in biblical idiom belonged more to the heart.

How it drifted

English has no living idiom that places feelings in the kidneys, so translators replace the organ with an abstract word. Once that happens, the pair is often flipped to suit modern English, where the heart is for feeling and the mind for thinking.

Used elsewhere in the period

The pair 'heart and kidneys' as what God tests is fixed in the Greek Old Testament: Psalm 7:10 LXX (ἐτάζων καρδίας καὶ νεφρούς), Jeremiah 11:20, 17:10 and 20:12. Psalm 16:7 says 'my kidneys instruct me in the night', and Psalm 73:21 has 'pierced in my kidneys' for inner anguish. The Dead Sea Scrolls hymns (1QH) use the same body language. Kidneys also appear in sacrifice (Leviticus 3:4): offered to God as the innermost parts.