“Evil and good are God's right hand and left.”
Philip James Bailey, in Festus (1839), misattribution of this to Mann seems to have only started in recent years, on the internet.
Misattributed
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Horace Mann 67
American politician 1796–1859Related quotes

“5241. To take from the right Hand, and give to the Left.”
Introductio ad prudentiam: Part II (1727), Gnomologia (1732)

“Is he alone who has courage on his right hand and faith on his left hand?”
As quoted in 1927 (2000) by Robert P. Fitton

“This morning, you can be on his right hand and his left hand if you serve. It's the only way in.”
1960s, The Drum Major Instinct (1968)

“This to the right, that to the left hand strays,
And all are wrong, but wrong in different ways.”
Ille sinistrorsum, hie dextrorsum abit : unus utrique
Error, sed variis illudit partibus.
Book II, satire iii, line 50 (trans. Conington)
Satires (c. 35 BC and 30 BC)

"The True Family and I" Address given in 16 countries (June and July 1995) http://www.unification.net/1995/950625.html

“God judged it better to bring good out of evil than to suffer no evil to exist.”
Enchiridion (c. 420 ), Ch. 27

“In God's providence there is no evil, but only good or its preparation.”
Thoughts and Aphorisms (1913), Jnana

https://hawzah.net/fa/Magazine/View/2689/3869/29058
Sunni Hadith