心安理得

xīn ān lǐ dé

with a clear conscience

Character by character

心xīn
heart

安ān
at ease

理lǐ
reason

得dé
obtained

这钱是我自己挣的，花得心安理得。

I earned this money myself, so I spend it with a clear conscience.

Tone: neutral.

Also critical: 拿了别人的钱还心安理得 means feeling no shame at all.

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