to rot away: to decay from the inside until what was whole falls apart
The picture behind every use of this verb is decomposition. Nothing here is smashed or cut down from outside. Something goes bad on its own, from within, the way a wound turns septic or fruit spoils on the branch. It is a slow, quiet, undignified way to come apart.
One image stretches across three very different subjects:
- a wound that stinks and festers in an unhealed body (Psalm 38:5)
- flesh, eyes, and tongue dissolving while the person is still standing upright (Zechariah 14:12)
- a whole people slowly coming apart under the weight of their own wrongdoing (Leviticus 26:39)
That third use is the one the Old Testament reaches for most. In Leviticus and three times in Ezekiel the verb is tied to the same little phrase, "in their iniquity," which is the striking part: guilt is not only punished from the outside, it corrodes the people carrying it. Ezekiel 33:10 even puts the word in the mouth of the exiles themselves, who say that they are rotting away in their sins and ask how they can possibly live.
Hebrew has neighboring words for related kinds of ruin: one for melting or losing solidity under heat or fear (מָסַס), and one for the rot that takes wood and reputations (רָקֵב). This verb sits between them. It is what living tissue does when it goes bad, and what a nation does when it is left to live with its own guilt.