Men of ill judgment ignore the good that lies within their hands, till they have lost it. Sophocles
Do good to both your own and to strangers as much as you can, and speak a kind word to both the good and the evil people. Ephrem the Syrian
Every man is guilty of all the good he did not do. Voltaire
He that can't endure the bad, will not live to see the good. Jewish Proverb
Chastise the good and he will mend, chastise the bad and he will grow worse. Italian Proverb
There's no bad without the good. Russian Proverb