Archaic KJV Word
Leasing
Modern equivalent: lies
What Was Lost
The Psalms' passionate hatred of lying. 'Seek after leasing' meant pursuing falsehood as a way of life -- making lies your treasure, your goal, your addiction. God destroys those who 'speak leasing' -- who make lying their native language. The word carried the weight of habitual, life-defining dishonesty that 'telling lies' cannot match.
Closest Survivor in Modern English
lese (as in lese-majesty -- an offense against sovereign truth/dignity)
Peak Usage (1611)
KJV Psalm 4:2 -- 'How long will ye love vanity, and seek after leasing?'; Psalm 5:6 -- 'Thou shalt destroy them that speak leasing'
Died ~1700
Completely displaced by the commercial real estate meaning. 'Leasing' as 'lying/falsehood' (from Old English leasung 'a lie') died when the word was captured by property rental contracts.
What Replaced It
“lies”
Generic; leasing specifically meant deliberate, habitual falsehood -- a lifestyle of deception
“falsehood”
Abstract; leasing was concrete and active -- the practice of lying
“deception”
Strategic; leasing was broader -- any form of untruth, from self-deception to public lying