do a bad turn

From LSJ

μὴ τὴν ὄψιν καλλωπίζου, ἀλλ' ἐν τοῖς ἐπιτηδεύμασιν ἴσθι καλός → Don't beautify your face, but be beautiful in your habits (Thales, in Diog. Laertius 1.37)

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