The Hebrew verb alach denotes moral corruption and filthiness — not merely external uncleanness but deep internal pollution of character. It is used in the Psalms to describe the universal sinfulness of humanity before a holy God.
The use of alach in Psalms 14 and 53 — 'They are corrupt, they do abominable works' — establishes the doctrine of total depravity. Paul quotes these psalms in Romans 3:9–12 to demonstrate that all humanity stands under condemnation.
This word calls the reader to recognize the depth of the human condition apart from grace. The corruption alach names is precisely what Christ came to undo — not through moral improvement but through divine regeneration (Ezekiel 36:26).