The quality or state of being hardened; becoming difficult or unfeeling.
From 'harden' (Old English 'heardian') plus '-ed' past participle plus '-ness' forming an abstract noun; describes a process of becoming hard or callous.
The 'hardenedness' of a heart became a common theme in religious and moral writing—it was the opposite of spiritual softening, a kind of soul crystallization that worried preachers deeply.
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