harden one's heart

Idioms  

1. Feel no sympathy for, as in We can't afford to give them more; we'll just have to harden our hearts when they ask. [Late 1300s]

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Example Sentences

"I am a judge of 35 years experience and I have seen in that time a lot of melancholy court cases which somewhat harden one's heart."

From BBC

"Often, when saying my prayers, I have wished I could forget him, but I can't, so I have to go on being uncharitable and in sin,—if indeed sin it be to harden one's heart against a bad man."

From Project Gutenberg

It certainly does harden one's heart," she said; "my heart is as hard as a diamond.

From Project Gutenberg

It is no comfort whatever that they are wonderfully beautiful creatures, striped and ringed with a thousand colors in a thousand various ways: one has only to see the riddled appearance of every leaf and flower to harden one's heart.

From Project Gutenberg

When things were hopeless, it was far better to recognize it and harden one's heart.

From Project Gutenberg