harder <PRO18 -19> A brother offended [is {harder} to be won] than a strong city: and [their] contentions [are] like the bars of a castle.
harder <JER5 -3> O LORD, [are] not thine eyes upon the truth? thou hast stricken them, but they have not grieved; thou hast consumed them, [but] they have refused to receive correction: they have made their faces {harder} than a rock; they have refused to
 return.
harder <EZE3 -9> As an adamant {harder} than flint have I made thy forehead: fear them not, neither be dismayed at their looks, though they [be] a rebellious house.

 
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