Archaic KJV Word
Quicken
Modern equivalent: make alive
What Was Lost
The sense of God jolting the spiritually dead into immediate, startling life -- not gradual recovery but instant resurrection of the soul. The 'quick and the dead' framing made quicken a word that straddled the boundary between life and death itself.
Closest Survivor in Modern English
vivify
Peak Usage (1611)
KJV Psalms, Pauline epistles -- 'quicken us together with Christ' (Eph 2:5)
Died ~1850
Victorian English narrowed 'quick' to mean 'fast'; the life-giving sense became opaque to readers who only knew speed.
What Replaced It
“make alive”
Loses the instantaneous, divine-agency dimension -- quickening implies God acting in a single moment
“revive”
Implies returning to a previous state; quicken could mean bringing life where none existed before
“give life”
Generic and passive; quicken carried the shock of sudden divine animation